Infrared spectrometry - ACS Publications - American Chemical Society

Chem. 1990, 62, 2722-7. (M42). Smith, A. D.; Gillis, K. M.; Ludden, J. N. Chem. Qeol. 1990, 81,. 17-22. (M43) Cotton, T. M.; Sheng, R.; Nl, F. Proc. S...
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Anal. Chem. 1002, 64, 270 R-302 R (M33) Bachman, W. J.; Stewart. J. T. J . Chfomatcgr. 1989, 481, 121-33. (M34) Turk, 0.C.; Kinsgton, H. M. J . A M I . At. Speclrom. 1990, 5 , 595-801. (M35) Qulnt, J.; Newton, J. F. Rugs Mann. S d . 1991, 47, 101-22. (M38) Relch, A. R.; Lucas-Reich, S.; Parvez. H. hog. HPLC 1988, 3 , 1-10. (M37) Vekamp. A. C.; Des. H. A,; Frei, R. W.; Brinkman, U. A. T. A M I . Chim. Acta 1900, 233, 181-9. (M38) Bradbury, D.; Elder, 0. R.; Dunn, M. J. hoc. Symp. Waste Menage. 1990, 2 , 327-9. (M39) Baldew, G. S.; De Goeij, J. J. M.; Vermeulen, N. P. E. J . Chromtogr. 1989, 498, 111-20. (M40) Rustum. A. M.; Ash, S.; Saxena, A.; Balu, K. J . Chmmtcgr. 1990, 514, 209-18.

(M41) Thelmer, K. H.; Krhran, V. Anal. Chem. 1090, 82, 2722-7. (M42) Smith, A. D.; oiiiis, K. M.; Ludden, J. N. chsm. W. 1990, 81, 17-22. (M43) Cotton, T. M.; Sheng, R.; NI, F. proc. SPE-Int. Soc. opt. Eng. 1990, 1336. 280-90. (M44) Sheng, R.; Ni. F.; Cotton, T. M. Anal. Chem. 1991, 83, 437-42. (M45) Ni. F.; Stteng, R.; Cotton, T. M. Anal. Chem. 1990, 82, 1958-83. (M48) Pothler, N. J.; Force, R. K. Anal. Chem. 1990, 82, 878-80. (M47) Soper, S. A.; Ratzlaff. K. L.; Kuwana, T. Anal. Chem. 1990. 62, 1438-44. (M48) Dutta, P. K.; Hammons, K.; Willibey, 6.; Haney, M. A. J . chrometogr. 1991, 538, 113-21. (M49) Yau, W. W. C. Eur. Pat. Appi. EP 380864 A2, 8 Aug. 1990; 9 pp.

Infrared Spectrometry Curtis L. Putzig,* M. Anne Leugers, Marianne L. McKelvy, Gary E.Mitchell, Richard A. Nyquist, Richard R.Papenfuss, and Lori Yurga Analytical Sciences Laboratory, 1897 Building, The Dow Chemical Company, Michigan Division, Midland, Michigan 48667

INTRODUCTION This review covers the published literature for the period late 1989 to late 1991 on aspects of infrared spectrometry that are relevant to chemical analysis. Our review has a strong bias toward papers published in English, or in certain aspects of IR spectrometry that are of particular interest to one or more of the coauthors. In addition, a few selected references to FT-Raman spectrometry are included for reasons given below.

which are strong in the Raman are usually weak in the IR, and vice versa in cases where the normal modes are allowed in both vibrational techniques. With the recent development of Fourier transform Raman (FT-Raman), it is now possible to rapidly record Raman spectra of most materials by using the FT-IR system equi ed with the FT-Raman option. FT-Raman is c o m m e r c i g available from several manufacturers, and we predict that in the future both IR and Raman ra will be recorded of materials on a routine basis for the e ucidation and identification of molecular structure. Therefore, we have included a few selected references to FT-Raman spectrometry for your convenience.

OVERVIEW OF ANALYTICAL INFRARED SPECTROMETRY Infrared radiation is usually defined as that electromagnetic radiation whose fre uency is between 14300 and 20 cm-’ (-0.7 and 500 pm). b i t h i n this region of the electromagnetic ,chemical compounds absorb IR radiation providing t ere is a dipole moment change during a normal molecular vibration, molecular rotation, molecular rotation-vibration, or a lattice mode or from combination, difference, and overtones of the normal molecular vibrations. The frequencies and intensities of the IR bands exhibited by a chemical compound uni uely characterize the qaterial, and-its IR spectrum can be use! to identlfy and quantify the particular substance in an unknown sample. Different classes of chemical compounds contain chemical oups which absorb IR radiation at essentially identical requency(ies) and have essentially the same band intensity(ies) wthin each class of compound, and these bands are termed “group frequencies”. Group frequencies are predictable and allow the anal t to elucidate and identify molecular structures without a v z b l e IR standard reference spectra for comparison. In addition IR spectra can be recorded ra idly of materials in the solid, liquid, solution, and vapor p ases over a wide range of temperature. Such studies aid in elucidatin the molecular structure of materials in different physic3 phases. Toda modern IR instrumentation allows spectra to be recorddof aam lea available in only low nanogram quantities or as low as hig picogram quantities using matrix isolation techni ues. No other technique allows examination and identdcation of materials under such a wide variety of hysical conditions, and it is this versatility that has allowed spectrometry to develop into the “work horse” of analytical science. One should be aware of the fact that Raman spectrometry is a complementary technique to IR spectrometry. In cases where a chemical compound has a center of symmetry, certain normal vibrations will only be active in the Raman and certain normal vibrations will only be active in the IR. Thus, one needs both techniques to record the com lete vibrational spectrum of many chemical compounds. horeover, bands

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(A) BOOKS Lin-Vien et al. have published a timely and excellent book integrating the characteristic IR and Raman fre uencies of organic molecules (AI). Duri edited books for t e applications of FT-IR spectrosco y fA2) and advances in the field of vibrational s ectra anzstructure (A3). George and #illis edited a book on com uter methods for UV, visible, and IR spectroscopy (A4). collection of IR spectra of common solvents has been published (A5). n edited a book on IR technology and a lications (A$%%% edited a book on chromatography/#IR (An Ferraro and Krishman edited a book on the application of FT-IR for industrial and laboratory chemical analysis (A8). Suzuki et al. edited a book on IR and Raman data base for the period June 1988 to May 1989 (A9).

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(B) REVIEWS A review of IR spectrometry covering the period 1985 to late 1989 has been ublished (BI). The review on polymer analysis including and Raman spectrometry covering the period December 1988 to November 1990 has been published (B2). Urban reviewed the literature on photoacoustic FT-IR of polymers with emphasis on the dynamics of small molecules in olymer networks and interfacial interaction (B3). Takeand Umenura reviewed the application of IR and Raman spectroscopyto the study of surface chemistry with emphasis on surfactants and their aqueous solutions, films, and adsorbed molecules at g-lid and liquid-solid interfa- (B4).%lea and Von Nagy-Felsoluki reviewed the ab initio calculations of vibrational band origins (B5).Scheiner reviewed the ab initio studies of the structure, energetics, and vibrational spectra of hydrogen bonded systems (B6). Davidson reviewed the characteristic vibrations of compounds containing the main-group elements I through VI11 (B7). Duncan reviewed the o of vibrational anharmonicity in molecules and the e f f e c t s x t the vibrational resonances have on the anharmonicity constants which may be extracted

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INFRARED SPECTROMETRY Curtis L. Putzlg is a Research Leader in the Instrumental Methods Group of the Analytical Laboratories, Dow Chemical USA. He received his B.S. degree from Wayne State University in 1971 and his M.S. degree in Analytical Chemistry from Purdue University in 1973. He joined The Dow Chemical Co. in 1973, and his career has been mainly in the fields of I R and Raman spectroscopy and Mass spectrometry. He is the author or coauthor of 17 publications. His research interests include the elucidation of molecular structure, polymer characterization, separation sciences, and the computer analysis of spectroscopic data.

Anma Leugem is a Research Leader in the Instrumental Methods group of the Analytical Sciences Laboratory at Dow Chemical USA, Midland MI. Anne received a B.S. degree in chemistry from Xavier University in Cincinnati, OH, and a W.D. degree in Physical Chemistry from the University of Cincinnati in 1981. She performed postdoctoral research at Syracuse University and University of Arizona before taking a research position in the paper industry studying the material science of paper. She joined Dow in 1984 where she began working in the area of fiber optic and Raman spectroscopy and detection. Anne's research interests include application of Raman and fiber optic spectroscopy to the chemical and morphological Characterization of synthetic polymers. Anne has received 2 US patents and has several disclosures filed. She has also authored six publications in the area of high-resolution and laser spectroscopy. Marlanno L. McKelvy is a Project Leader in the Polymeric Materials Research Center of the Analytical Sciences Laboratories of Dow Chemical USA, Midland, MI. She received a B.S. degree from the University of Detroit, Detroit. M I (1979), an M.S. degree (1982) and a Ph.D. (1985) from Polytechnic University, Brooklyn, NY. Subsequently, she joined the Analytical Sciences Laboratories where she is Involved in solving polymer problems using infrared spectroscopy. Her research interests involve the characterization of polymers using vibrational spectroscopy and infrared microspectroscopy. She is a member of the Society for Applied Spectroscopy and the Coblentz Society.

Rlchard A. Nyquist is a Senior Associate Scientist in the InstrumentalMethods Group of the Analytical Sciences Laboratory, Dow Chemical USA. He received his B.A. degree in chemistry from Augustana College, Rock Island, IL, and his M.S. from Oklahoma State University. He joined The Dow Chemical Co. in 1953, and his career has been mainly in the field of vibrational spectroscopy. He utilizes IR and Raman spectroscopy for solving chemical problems, for the elucidation of molecular structure, and for qualitative and quantitative analyses. Nyquist is the author or coauthor of over 140 scientific articles including books, chap ters in books, and patents. He is a member of The American Chemical Society, The Society for Applied Spectroscopy, and ASTM E l 3 on molecular spectroscopy. I n 1985 he received the Williams-Wright Award for his contributions to industrial infrared spectroscopy from the Coblentz Society, and in 1989 he received an ASTM Award of Appreciation for his leadership and work with ASTM E13. Nyquist was a National Tour Speaker for the Society of Applied Spectroscopy in 1989. Rkhard R. Papenfuss Is a Research Associate with the Poiymeric Materials Research Center, Dow Chemical USA. He received his B.S. degree from Wisconsin State College at LaCross. He joined Dow Chemical in 1963, and has worked in the Inorganic, Organic, and Agricultural Products Groups. For the last 14 years he has concentrated in applying both qualitative and quantitative infrared spectroscopy to polymeric systems. I n addition to continuing his work in infrared, he is currently applying gas chromatography/matrix isolation/infrared spectroscopy to polymeric and other related materials.

Lor1 Yurga is a Senior Research Chemist in the Agricultural Analysis Group of the Analytical Sciences Laboratories, Dow Chemical USA. She received a B.S. degree in chemistry and biology from Central Michigan University and joined the Dow Chemical Co. in 1983. She spent 2 years in methods development in the Organic Products Group prior to her assignment to the Instrumental Methods Group where her expertise was concentrated in problem soking using infrared and Raman spectroscopy. Her research interests are in the development and utilization of hyphenated techniques combining chromatography and infrared spectroscopy. She currently serves as the Quality Performance Coordinator for the Analytical Sciences Laboratory. ~

Gary M l t c M is a Project Leader in the Instrumental Methods group of the Analytical Sciences Laboratory of Dow Chemical USA in MMland, MI. He obtained a B.S. degree in Chemistry in 1977 from Wayne State University in Detroit and shortly after joined the Physical Chemistry Department of the GM Research Laboratory where he worked in the area of Surface Science. He receked a Ph.D. in Physical Chemistry in 1987 from the University of Texas at Austin. His dissertation work involved the study of the adsorption and reaction of small molecules on platinum surfaces. Gary's current research interests include applying high-resolution electron energy loss spectroscopy, X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and other techniques to understanding the structure and chemistry of polymer surfaces. I

from spectral data (& Ashley I). reviewed the recent advances and applications of IR spectro electrochemistry to probe the electrodesolution interface (B9). McQuillan reviewed FT-IR studies of coatings and adsorbed species at electrode surfaces (BIO). Tarte et al. reviewed the application of vibrational spectroscopy to the field of solid state chemistry (B11). Norrby reviewed the factor point space groups and its application to vibrational spectroscopy on crystalline solids (B12). Fierro reviewed the application of IR in determining the interaction of adsorbed molecules on the catalyst surface (B13). Allen and Palen reviewed recent advances in aerosol analysis by application of IR (B14). Mirabella has reviewed the ap-

plication of ATR/IR for quantitative analysis (B15). Bernath reviewed the application of high-resolution IR of transient molecules (B16). Quack reviewed current experimental technique of coupled vibrations in polyatomic molecules (BI 7). Little and Durig reviewed theoretical considerations and experimental results for far-IR spectra of vapors (B18). Suzuki reviewed the IR and h a n literature data base for the period June 1989 to May 1990 (B19).Schrader reviewed Rand Raman (B20). Davidson reviewed micromethods using I the vibrational spectra of coordinated ligands (B21).Flaud reviewed the application of IR in the study of the atmosphere (B22). Wurrey and Gurka reviewed environmental applications of GC/FT-IR (B23). Pohle reviewed the application of IR in the study of DNA complexes (B24). Urban and Koenig reviewed recent developments in depth profiling from surfaces using FT-IR (B25). Lipp and Smith reviewed the applications of IR, Raman, and near-IR in the analysis of silicones (B26). Browne et al. reviewed IR as an in situ probe for catalytic surfaces (B27). Willis reviewed process applications of IR (B28). Handke et al. reviewed the theory and experimental problems using external reflection FT-IR (B29).Markovich and Pidgion reviewed the application of FT-IR in the pharmaceutical sciences (B30). DeBlase and Compton reviewed the experimental and theoretical aspects of IR emmission spectroscopy (B31). Bauschlicher and Langhoff reviewed the ab initio methods for radiative rotational, vibrational, and electronic transitions ANALYTICAL CHEMISTRY, VOL. 64, NO. 12, JUNE 15, 1992

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of molecules (B32). Back reviewed the basic concepts and experimental techniques for utilizing FT-IR in the analysis of thin inor anic films (B33). Deylin reviewed the vibrational spectra ant! point defect activities of icy solids (ice I) and gas-phase clusters (B34). Diem reviewed the mstrumentation required for obtaining vibrational optical activity information on molecules (B35). Sandorfy et al. reviewed the IR studies of the biologically important hydrogen bonds in halogen-containing solvents (B36). Miller reviewed the field of vibrational spectroscopy of weakly bound complexes (B37). Crompton reviewed the methods of anal sis for organosilicon compounds including IR (B38). Siesir reviewed the determination of structural changes induced by various mechnaical treatments by application of recent FT-IR techni ues (B39). Urban has reviewed the analysis of olymers an\ coatings by a plication of photoacoustic FT-fR (B40). Ogilvie reviewed t e pro res8 in the experimental measurement and the theoreticaf interpretation of the vibrationalrotational spectra of diatomic molecules (em hasis on HCl and CO) during the period of 1889-1988 (B41f Katon et al. reviewed IR microspectroscopy instrumentation, sample handling, and applications (B42). Jackson et al. reviewed the application of FT-IR to the study of the structure and function of lipids, polypeptides, and proteins (B43). Christensen and Hamnett reviewed the theory of external and internal IR reflection and transmission of electrodeelectrolyte interfaces (B44).Durig et al. reviewed the far IR data and theoretical calculations for haloacetyl halides (B45). Lacroix et al. reviewed GC/FT-IR for biomedical a plications (B46). Wilson and Childers reviewed the recent agances in the matrix isolation IR s ectrometry or or anic molecules (B47). Wurrey reviewed tRe a plication G F/!T (R Iin environmental analyses (B48). 8roasmun and McGorrin reviewed GC-matrix isolation FT-IR for the analysis of generated aroma compounds (B49). Jacox and Thompson reviewed recent developments in matrix isolation spectrosco y of molecular ions isolated it? solid Robertson ani de Haseth reviewed the references neon (BO). for an interface that can accommodate both normal and reverse phase solvent systems, as well as gradient elution systems (B51). Wieboldt et al. made an introductory review of supercritical fluid chromatography/FT-IR. The use of COZ as a super critical fluid is treated in detail (B52). Andrews reviewed the experimental requirements, instrumental advantages, and examples of FT-IR of matrix isolated species (B53). Norton reviewed a common approach for measuring FT-IR spectra from coupled GC, SFC, or HPLC with only minor chan es in the hardware required (B54). ~alissa et al. reviewed &/FT-IR applicationsin organic trace analysis (B55). Ryberg reviewed IR spectroscopy of molecules adsorbed on metal surfaces (B56). Pohle and Fritzsche reviewed IR as a tool for the study of DNA structure and DNA-lignand interactions (B57). Mantsch and McElhane reviewed ap lications of IR to biology and medicine (85833 Ferraro anzMaroni reviewed the characterization of high-critical-temperature ceramic superconductors by application of vibrational spectroscopy (B59). Niki and Maker reviewed the study of atmospheric reactions of h drocarbons usin FT-IR (B60). Davidson reviewed the appication of IR anfRaman in the study of actinide, transition metal, and rare earth containing com ounds (I3611 and of coordinated ligands (B62). Reffner and gihlborg reviewed the field of microanalysis using reflectance FT-IR microscopy (B63). Baraldi reviewed IR emission spectroscopy applications (B64).Watts reviewed IR predissociation spectroscopy of van der Waal clusters (B65). Yarwood reviewed FT-IR in the study of ultrathin organic films (B66, B67). Gussoni et al. reviewed the current state-of-the-art in the field of vibrational intensity (B68).De la Cruz and She pard reviewed the carbonyl stretching frequencies for carionyl li ands in metal coordination compounds or clusters (B69). T%ornton reviewed the IR s ectra of metal @-ketoenolates and related complexes (B70f Fredericks reviewed the application of IR in the analysis of coal liquids (B71). Chang et al. reviewed the development in electrochemical IR for the adsorption of CO on low-index Pt and Rh surfaces aqueous solution and ultrahigh vacuum environments (B72). Poll has reviewed the recent work on solid hydrogen using IR

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and Raman (B73). Fritzsche reviewed IR and IR linear dichroism of nucleic acids (B74). Le Gal et al. reviewed applications of IR for structural studies of cells and bacteria (B75). Barrett reviewed structural studies of sulfenic acids, sulfenate esters, sulfenyl halides, and sulfuranes (B76). Aslanian reviewed applications of Raman and IR to study chemical transmission in the nervous system (B77). Urban et al. reviewed the application of photoacoustic FT-IR for probing polymer structures (B78). Warr has reviewed spectral data bases including IR, NMR, and MS and spectral data collection, quality control and software (B79). Lucaa has reviewed recent develo ments and Bates future trends in the application of IR as a sensor of IR for monitoring comet al. has reviewed amlications .. bustion (B81). Ciealak-Golonkareviewed the techniques (including IR and Raman) used in the identification of inornanic comDounds containing chromium (VI) species ( ~ 8 2 )Milhaeelian . riviewed the subject of data treatment in the ap lication of hotoacoustic FT-IR (B83). Parker revieweidis ersive Fourier transform spectroscopy as a technique for teterminin the optical constants of solids, liquids, and gases from Arect measurements of both the amplitude and hase of either their reflection or transmission coefficients (f;84). Le Gal et al. reviewed the ap lication of FT-IR for the Won . and Mantsch have analysis of cells and bacteria (My described the pressure-tuning technique k r obtaini IR and Raman spectra of aqueous surfactant solutions (B83.Fredericks reviewed applications of IR for the analysis of cool liquids (B87).

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(C) FAR INFRARED A study of the far-IR spectrum of the C4 radical roduced by t r a p p y the products of the W photolysis of 1,3-&adiene and acet ene in vibration at 172.4 cm-’ was reported by Withey, ghen, and Graham (Cl).Durig et al. discussed the conformational stability, barriers to internal rotation, ab initio calculations, and vibrational assignment of fluoroacetyl fluoride (C2). Durig, Godbey, and Larsen reported on the far-IR spectra and conformational stability of the epihalohydrins (C3). Zahn et al. reported on the usefulness of combining Raman and IR spectroscopy to study semiconductor interfaces (C4). The microwave and far-infrared spectra were analyzed and discussed b Eggimann et al. in light of ab initio geometry calculations (85). Durig et al. discussed the conformational stability, barriers to internal rotation, vibrational assignment, and ab initio calculations of 2-chloropropenoyl fluoride (C6). Durig and Lindsay measured the far IR spectra of ethyl nitrate and were able to calculate the barriers to internal rotation (C7).The far IR spectrum, conformational stability, barriers to internal rotation, ab initio calculations, and vibrational assignment of propionyl chloride was reported by D u y et al. (C8). Bowmaker et al. discussed the structural and far R studies of compounds containing the novel trinuclear iodocuprate(1) com lex [Cu3(AsPhJ314](C9). Durig and Larsen discussed the vilrations and barriers to internal rotation for ethanol and 2,2,2-trifluoroethanol (CIO).The far IR spectrum, conformational stability, barriers to internal rotation, normal coordinate calculations, and vibrational assi ment for chloroacetaldehyde was reported by Durig et al. (81) Gatesman . et al. re orted on the optical properties of polycrystalline diamond glms in the far IR (C12). The far IR spectrum, barrier to internal rotation, ab initio calculations, and ro structure for acetylacetylene was discussed by Duri et al. (C13). Conformational stability, barriers to intern3 rotation, RHF/STO-3G* calculations, and vibrational esignment of 2-bromopropenoyl fluoride was reported by D et al. ((714). Durig, Guir is, and Phan discussed the far% spectrum, conformationaf stability, barriers to internal rotation, ab initio calculations, and vibrational assignment of pro ionyl bromide (C15). Marteau and Obriot developed and evakated a far IR multiple-path cell without internal mirrors (C16). (D) NEAR-INFRARED TECHNIQUES AND APPLICATIONS A general discussion of near-infrared analysis, addressing sample collection and presentation, calibration a proaches, and calibration testing, was given by Weyer (D1). golubilities

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of water and or anic components in slightly cross-linked poly(vin 1alcohc!) were measured in the presence of binary aqueous %quidmixtures at different temperatures using NIR s ctroscopy as well as gas chromatography by Hauser et al. The quantitative analysis of solutions containing various concentrations of sodium hydroxide, sodium chloride and sodium carbonate over the r e 0-16% m/m was carried out using NIR spectroscopy byTrant, Davies, and Bilverstone ( 0 3 ) . Roberson et al. used near-IR laser diode intracavity absorption spectroscopy to determine the concentration of ionic surfactants complexed with laser dyes ( 0 4 ) . NIR reflectance spectroscopy was used to characterize the bitumen Content of oil sand samples which represented a variety of ores as well as mud and silt de osita containing small quantities of bitumen by Dougan. &e potential of this techni ue for on-line analysis was also discussed (05). A method lor the determination of several petro hysical and etrochemical roperties was explored using N R ! analysis. ?phis procedure o!r eampling and analyeis was described in a patent disclosure b Difo gio (06).A simple method for the measurement of IR re ectance s ectra of samples of limited size (100mg) . et al. was developed ancfdiscussed by Davies (07)Schrader discussed several possibilities for matching a microsample to a spectrometer for NIR and FT-Raman spectroscopic analysis (08). Buxton and Mertens conducted a thorough study to assess the reliability of NIR reflectance spectroscopy for the anal sis of forages. They found that unless NIR results are checied for bias in subsets and verified by conventional anal sea, erroneous conclusions could be drawn using NIR resdts (09). The analysis of sugar content of beverages was accomplished by analyzing the nonvolatile residues of the liquid samples which were retained on fiberglass filters and measured usin NIR reflectance spectroscopy by Alfaro, Meurens, and h r t h (D10).A theoretical basis for NIR measurements in feed analysis was obtained from the study of artificial mixtures of ure chemicals by Wetherill, Murray, and Glasbey (011). A d !iscussion of the effect of particle size on the NIR reflectance spectrum and quantitative analyses based on NIR measurements was given by Bull (012). Wright, Birkett, and Gambino used NIR reflectance spectroscopy to analyze the pul yield and cellulose content of wood in the powder form. $he NIR measurements correlated well with other lab techniques (013). The uality of hybrid bermudagrasa was assessed using NIR relectance spectroscopy by Barton, Burton, and Monson ( 0 1 4 ) . NIR reflectance s ectroscopy and factorial discriminant analysis was usex to classify the method of manufacture of commercial skim milk powders by Downey et al. (015).

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(E)IN SITU General Chemical Applications. Kellar et al. performed t studies of the fluorite/oleate system at pH 9.1 and in situ E found spectral data which indicated that thermotropic phase transitions of chemisorbed calcium oleate occur at the fluorite surface (El). In another paper, Kellar, Cross, and Miller discussed the use of the near infrared for the analysis of surfactant adsorption studies on fluorite in situ (E2). Sperline and Freiser coated a total internal reflection element with a highly viscous hydrocarbon liquid and measured the IR spectra with the element in contact with aqueous solutions. uantitation and kinetics of adsor tion and migration of s e m i c a b into the film was obtainef(E3). Doyle discussed the design and application of a deep immersion probe for in situ monitoring a lab scale reaction (E4). In situ IR spectroscopy was used to study the phase changes of gypsum durin its dehydration b Putnis, Widkler, and FernandezDiaz b5).Purohit, Rotgschild, and Ehrlich performed an in situ stud of the W photochemistry of adsorbed titanium tetrachloriie by IR spectroscopy (E6). Gas-phase IR spectroscop was used to determine the distribution of products from a $ow reactor in which methyl chloride was reacted with silicon in the presence of a copper catalyst by Friedrich et al. ( E n . The type of complexes that salicylate forms with the surface of oethite in aqueous media were studied in situ using ylindric3 internal reflection IR spectroscopy by Yost, ejedor-Tejedor,and Anderson (E8).Using a polymer-clad optical fiber as the internal reflection element, Degrandpre and Burgess measured FT-NIR spectra of various non olar or anic solvents which migrated into the polymer clacfdin The reaction of oxidized activated carbon surfaces wit!

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gaseous ammonia, water, and hydrogen was studied usin in situ IR spectroscopy by Meldrum and Rochester (EIO).+he same authors also described an in situ diffuse reflectance IR study of the heat treatment of activated carbon in situ in oxygen at 298-853 K ( E l l ) . Young and Spicer reported the first results of a combined in situ IR and EXAFS study of a matrix isolated molecule, dibromomethane (E12). The photocorrosion of n-silicon in ammonium fluoride solutions was studied using in situ attenuated total reflectance spectroscopy in the IR b Peter, Blackwood, and Pons (E13). The consecutive immob&ation of (3-aminopropyl)triethoxysilane and glutaraldehyde on chalcogenide IR transparent optical fiber surfaces was studied usin the optical fiber as the ATR element by Taga, Weigel, an! Kellner (E14). An in situ investigation of the adsorption of proteins and polysaccharides in aqueous-olid interfaces was performed using internal reflection spectroscopy in the IR by Ishida and Griffiths (E15). Polymer Studies. The development and application of a high-temperature IR cell for in situ sample monitoring was reported by K wicz (E16). Margalit et al. reported on the use of silver fiber optic evanescent wave spectroscopy for in situ monitoring of the chemical processes in adhesive curing (El7). Snyder discussed the in situ IR analysis of polyimide curin (E18).The use of sapphire optical fibers as in situ multipk internal reflection elements for monitoring reactions of polymers was reported by Druy et al. (E19). Fasce, Galante, and Williams reported on the curing of epoxy resins with in situ generated substituted ureas (E20). The development and application of a method to study in situ photopolymerization using IR spectroscopy was discussed by Udagawa, Sakurai, and Takahashi (E21). George et al. discussed the real-time monitoring of the cure reaction of a tetraglycidyl4,4'-diaminodiphenylmethane (TGDDM)/DDS epoxy resin using IR spectroscopy with fiber optics (E22). Film Formation Studies. An in situ study of the silicon-hydrogen bond in amorphous hydrogenated silicon ultrathin films was reported by Blayo, Blom, and Drevillon (E23). Wadayama et al. discussed the in situ IR observation of photochemically deposited silicon nitride thin films (E24). Zip el, Breiter, and Kellner investigated the adsorption of carton monoxide on platinum and palladium surfaces by in situ ATR spectroscopy in the IR (E25). The application of reflectance-difference spectroscopy in the IR to real-time in situ analysis of film growth was reported by Colas et al. (E26). In situ IR investigations of polymer surface modification in downstream microwave plasma etchin was discussed by Leu and Jensen (E27). The growth of hydirogenated amorphous Si f i s on Al substrates in a flow reactor was studied in situ usin IR reflection absorption spectroscopy by Toyoshima et al. (428).O'Neill, Singh, and Gifford reported on the in situ IR absorption techniques employed to characterize the as phase plasma species and etch products present in halocar%on containing lasmas (E29). In situ IR ellipsometry was used to study t1e vibrational properties and the growth of amorphous semiconductor ultrathin films by Blayo, Drevillon, and Huc (E30). Wadayama et al. reported on the in situ IR spectroscopic observation of amor hous hydrogenated fluorinated silicon films growing un er spontaneous chemical deposition method (E31). In situ IR spectroscopy was applied to the analysis of film formation during low-pressure chemical vapor deposition of tungsten by Kobayashi, Goto, and Suzuki (E32). The same authors also reported a study of the mechanism of selective chemical vapor deposition of tungsten using in situ IR spectroscopy and Auger electron spectroscopy (E33, E34). Catalysis Studies. The adsor tion and reaction of a CO-CO,-H, mixture on supportecf Cu catalysts has been investigated using in situ IR spectroscopy with a h pressure cell by Burch, Chalker, and Pritchard (35). Van er Grift et al. reported on the characterization of copper-silica catalysts using in situ diffuse reflectance IR spectroscopy (E36). The in situ observation of molybenum-oxygen stretching vibrations during the reduction of molybdena with hydro en using diffuse reflectance IR spectroscopy was discussed %yHirata (E37). Kanno, Ohsumi, and Kobayashi reported the development of a flow reactor coupled to an IR spectrometer to study the transient behavior of adsorption and desorption of CO and C02on a MgO catalyst (E38).The characterization of the adsorbed state of isoprene on alumina and copperalumina catalysts using carbon-13 NMR and in situ diffuse

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reflectance IR spectroscopy was reported by Rigole et al. (E39). An in situ resonance Raman and IR study of hexacyanoferrate(I1) ion adsorbed to aqueous colloidal titanium dioxide was discussed by Umapathy, McQuillan, and Hester (E40). An in situ EXAFS and IR study of the dynamic behavior of a Si02-attached rhodium dimer during metal-assisted hydroformylation was conduded by Asakura et al. (E41). Sakata et al. reported on the carbon-hydrogen exchange reaction of methoxide species on SmO, catalyst usin in situ IR spectroscopy (E42). Studies using diffuse retfectance IR spectroscopy for kinetic and mechanistic studies of carbon dioxide hydrogenation in a continuous recycle reador were conducted and reported by Prairie, Highfield, and Renken (E43). Kamble, Gupta, and Iyer reported on the in situ IR studies of carbon monoxide and carcon dioxide adsorption on NaX zeolites (E44). The IR in situ characterization of HY zeolite acid sites during cyclohexene transformation was discussed by Joly et al. (E45).Lavalley, Maache, and Saussey conducted in situ IR studies of the reaction mechanisms of several catalyst systems (E46). A high-pressure, high-temperature in situ IR study of carbon monoxide hydro en reactions over rhodium silica catalysts was reportedby Andierson et al. (E47). Highfield, Prairie, and Renken discussed the development and application of an in situ IR cell coupled to a continuous recycle reactor for catalytic process research (E48).Carbon monoxide hydrogenation on silica-supported iron and ruthenium catalysts was studied using in situ IR spectroscopy by Schanke et al. (E49). Benitez et al. reported the in situ diffuse reflectance study of adsorbed species in the hydrogenation of carbon oxides (E50). Electrochemical Studies. Habib and Maheswari conducted in situ IR studies of the electrochromic reactions of tungsten trioxide films (E51).In situ IR studies of redox active self-assembled monola erg on gold electrode surfaces were performed and reportedrby Bae et al. (E52). Christensen and Hamnett discussed the in situ IR investigationsof the growth, electrochemical cycling, and overoxidation of polypyrrole in aqueous solution (E53). Yau et al. reported on the use of atomic-resolution scanning tunnelin microscopy and IR spectroscopy as combined in situ proEes of electrochemical adlayer structure with res ect to the carbon monoxide on rhodium(ll1) and system ( f 5 4 ) . Rasch, Novak, and Vielstich conducted electrochemical and in situ IR investigations on polythiophene in prop lene carbonate (E55). The development of a sample switciing interface for the measurement of IR spectra of electrode surfaces was reported by Faguy et al. (E56).Modeling the in situ IR reflection-absorption s ectra of the diffUse layer was discussed by Faguy et al. (E57). kelar, Cross, and Miller re orted on the adsorption density calculations from in situ PR internal reflection s ectroscopy data at dilute surfactant concentrations (E58). C k g and Weaver investigated carbon monoxide adsorbed on ordered platinum(lOO)-aqueous interfaces using in situ IR spectroscopy. The discussed the double-layer effects upon the adsorbate bingng geometry (E59). Chan and Weaver also reported on the in situ IR spectroscopy o f carbon monoxide adsorbed on ordered platinum(ll0)-aqueous interfaces (E60).Further studies of carbon monoxide were conducted by Chang and Weaver where CO was elechosorbed on ordered rhodium(100) and investigated using in situ IR spectroscopy (E61).Chang and Weaver discussed the comparison of carbon monoxide at single-crystal metal electrodes and CO behavior at metal surfaces in ultrahigh vacuum (E62). In situ IR electrochemical studies of cyanide adsorbed on platinum and palladium were reported by Ashley et al (E63). Ozanam and Chazalviel conducted in situ IR studies of the early stages of silicon interfacial oxidation with a nonaqueous electrolyte (E64). The adsorption and oxidation of carbon monoxide on platinum was studied using a gas diffusion cell and in situ IR spectroscopy by Lu and Bewick (E&). Yu and Lam ert reported the in situ IR studies of electrochromic hydraJnicke1 oxide films (E66).Platinum particles dispersed in Nafon films on old electrodes were studied using in situ IR spectroscopy by bsawa et al. (E67).An in situ IR study of metal cyano-complexes in the presence of trications was reported by Taniguchi et al. (EM). Kunimatsu, Samant, and Seki discussed the study of bisulfate and sulfate adsorption on a platinum electrode (E69). An in situ analysis of carbon monoxide during chemisorption and oxidation on graphite-supported platinum using IR microspectroscopy was reported by Self and Sermon (E70). 274R

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Lu et al. reported the im rovement in cell design and estimation of the solution thicLess for in situ IR electrochemical measurements (E71). An in situ internal reflection IR investigation of the growth mechanism of polyphenylene during electrooxidation of bi henyl in meth lene chloride was discussed by Pham et al. 8372). Islam aniKunimatsu conducted in situ IR studies of adsorbed intermediates in electroduction of carbon monoxide on copper in aqueous potassium bicarbonate (E73). The chlorine evolution reaction was studied comparatively at Ru/Ti, Ir/Ti, and (Ir + Ru)/Ti mixed oxides by a combination of electrochemical and in situ photoacoustic techniques with ex situ Rutherford scattering measurements by Vallet, Heatherly, and White (E74). Samant et al. reported an in situ IR study of the adsorption geometry of bisulfate accepted ions on a platinum electrode (E75). An in situ IR study of adsorption and oxidation of methanol on sputtered latinum electrodes in sulfuric acid solution was discussed by !ham et al. (E76). Stole and Porter conducted studies using in situ external reflection IR spectroscopy as a probe of the interactions a t the liquid-solid interface of long-chain alkanethiol monolayers at gold (E77).Oxidation state changes of molecules irreversibly adsorbed on electrode surfaces as monitored by in situ IR reflection absorption spectroscopy were discussed by Sasaki et al. (E78).Self and Sermon reported the use of in situ IR microspectrometry to study the spatial differentiation of carbon monoxide during chemisorption and oxidation on hi hly oriented graphite-supported platinum (E79). An in situ fR reflection absorption study of glucose oxidation on platinum in acid was reported by Bae et al. (2380). Neugebauer et al. conducted in situ IR studies of iron electrodes in acid solution using internal reflection spectroscopy (E81).Further work investigating iron electrodes in acid solution was performed using external reflection absorption IR spectroscopy by Tschinkel, Neugebauer, and Neckel (E82). Faguy et al. reported an in situ study of bisulfate adsorption on platinum(ll1) single-crystalelectrodes using in situ IR s ectroscopy (E83). An in situ IR study of carbon dioxide rduction at platinum, gold, and glasay carbon electrodes in acetonitrile was conducted by Christensen et al. (E84). Seeger, Kowalchyk, and Korzeniewski repoted the in situ IR analysis of polymer-dopant interactions in olyaniline-modified electrodes (E85). In situ IR and XPZstudies of the hexacyanoferrate redox system was reported by Datta and Datta (E86).Kunimatsu studied the electrooxidation of methanol on platinum using in situ IR spectroscopy (E87). Huang et al. reported the in situ IR studies of the cadmiumunderpotential deposition mediated reduction of nitrate on gold (E88).In situ IR evidence for the electrochemical incorporation of hydrogen into silicon and germanium was observed by Mandal, Ozanam, and Chazalviel (E89). An in situ IR study of the electrochemical dopin undoping process of Pham and Moslih poly(1-naphthol) film was discussed (E90).Rao, Ozanam, and Chazalviel reported the in situ IR study of the silicon surface in hydrogen fluoride electrolyte (E91). In situ IR studies of the effects of tin on the electrochemical oxidation of carbon monoxide on polycrystalline platinum was reported by Bae, Sasaki, and Scherson (E92). Rao, Ozanam, and Chazalviel reported the in situ electromodulated IR study of porous silicon formation (E93). An in situ IR study of the adsorption behavior of cyanide ions on a platinum electrode was discussed by Datta and Datta (E94). Zotti and Schiavon reported the evolution of in situ conductivity of polythiophene deposits by potential cyclin (E95).Electrochemical and in situ IR studies were performe! by Novak and Vielstich to characterize polypyrroles (E96). Samant et al. reported on the theory and application of vibrational spectrosco y to contact adsorbed thiocyanate on silver electrodes ( E 9 8 . The study of the influence of calcium ions on carbon monoxide adsorption at a platinum electrode using in situ IR spectrosco y was performed by h a m a t a and Enyo (E98). Huang et !a discussed the use of in situ IR spectrosco y to study the reduction of carbon dioxide on polycrystakne platinum in acid solutions (E99). Pham, Moslih,and Camille reported the study of the mechanism and film structure in the electrochemical oxidation of 2-naphthol using in situ IR s ectroscopy (Elm).An in situ IR study of the adsorption ofcarbon monoxide on a polycrystalline ruthenium electrode was conducted by Gutierrez, Caram, and Beden (E101).Cooper et al. reported the investigation of the redox states of p-~yanodicyanotetrakis(2,2’-bipyridine)di-

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ruthenium(+) and evidence of valence delocalization of the singly oxidized complex (E102). The application of in situ IR spectrosco y to the study of surface films formed on lithium and no%le metals at low potentials in lithium battery electrolytes was reported by Goren, Chusid, and Aurbach (E103).

(F) ON-LINE A method and application for the determination of semiconductor processing chemicals by NIR s ectrosco was disclosed in a patent application by Koashi, Akota, an&anai (FI). Another patent ap lication was described by Shih, Chang, and Val1 for the &termination of phosphate layer thickneee and composition of a hos hate coated surface using IR reflectance spectroscopy (&I. 8ontinuous monitoring of beet sugar with an on-line NIR spectrometer was discussed b Marchetti (F3). A visible/NIR spectral database for pkbnium solutions of known nitric acid, fluoride, and oxalate composition is being developed by Day, Vigil, and Marsh at Los Alamos National Labs to be able to monitor the process solutions at the Los Alamos Plutonium Facility (F4). Analysis of the h drogenation of vegetable oil in margarine manufacture using I& s ectroscopy with attenuated total reflection was discussedy! Sadeghi-Jorabchi et al. (F5). The use of on-line IR spectroscopy under plant conditions to measure com osition of 01 er blends and copolymers exiting an extruler was s t u i e g y McPeters (F6). Stengler and Weis designed and applied a high-pressure, high-temperature flow cell for the on-line IR analysis of molten polymers. They found it was possible to determine the presence and amount of additives, control the polymerization process, and control the end grou s (F7). A process and apparatus for controllin the manugcture of polymers using IR s ectroscop was iescribed by Laurent, Martens, and Vidal &B). In anode, paper, these authors, Martens, Vidal, and Laurent, described a rocess and IR spectrometer for the manufacture of olyoxy8kylenes (F9). “he tem rature of a natural gas flame and the temperature in a heate& jet were measured with IR spectroscopy using an absorption band of C02by Shanam et al. (F10).An online measurement system was described to detect the dew point and CO gas concentration simultaneously in a hi h temper(F11) ature furnace using IR absorption by Iuchi and H&o Zabielski, Egolf, and Hollick reported the successful results of a pro’ect to control the fuellair ratio on industrial burners using emission spectroscopy of natural gas flames ( ~ 1 2 ) . A technique was developed by Maeda, Takahashi, and Kuwan0 for the in situ determination of gas components such as CO, COz, and H 2 0 at p ometallurgical temperatures eater than lo00 “C (FI3). r p a t e n t disclosure was fiied by Rewelling et al. using IR spectroscopy to determine the concentrations of anesthetics in a respiratory as stream of an anesthetized patient (F14).A 1-m-diameter,teflon-coated, stainless steel s here was constructed as a tool for conducting IR studies of tge atmospheric chemistry of toxic chemicals by Stone (F15). The chamber was equipped with an in situ, multipass optical system which allows an IR pathlength of 106 m to be used for the analysis. IR transmitting zirconium fluoride optical fiber cables were used in one installation, to separate an FTIR spectrometer 50 m from the sensor location where remote flow through abso tion cells were used for the measurement of gases and liquix (3’16). Infrared fiber optic sensors for the remote detection of hydrocarbons operating in the 3.3-3.6-pm re ion 7). were developed and discussed by Matson and Griffin A noninvasive method for monitorin ethanol in fermentation processes using fiber optic based N R spectroscopy was devel0 ed and re orted by Cavinato et al. (FIB).Far uharson et develope: a fiber optically coupled FTIR aniyzer for the on-line analysis of extruded polymers (F19). A patent relating to an apparatus and method for NIR reflectance analyses of successive samples was disclosed by Johnsen for the measurement of composition of viscous or solid materials (F20). Herrala, Niemela, and Hannula devel0 d a miniature FTIR spectrometer for industrial on-line a pEations (F21). New techniques and accessories for the Ig analysis of liquids and solids in on-line and off-line sampIing were discussed by Tregidgo (F22). The fadors affecting performanceof rugged multiwavelength NIR and IR analyzers for industrial process measurements were discussed by Hy-

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varinen and Niemela (F23). The development of a continuous on-line automatic NIR analyzer was disclosed in a patent application by Lapeyre et al. (F24). Doyle and Jennings discussed the development of a deep immersion probe that can be interfaced to the FTIR spectrometer to produce attenuated total reflectance spectra (F2.5). Thompson discussed the use of statistics in calibrating and validating NIR on-line analyzers (F26). The history and future of process analyzer maintenance was discussed by Wright (F27). McCurley reported on the remote troubleshooting and predictive maintenance for process analyzers and systems (8’28).

(G) ENVIRONMENTAL ANALYSIS Devir et al. (GI) examined the water continuum in the 15-25-pm region of the spectrum and found evidence for the presence of water dimer in the atmosphere. Carrieri (G2) re orted that the strong mid-IR bands of contaminant 1iquid)s wetting soil and sand can be remotely detected by 0.103-eV laser irradiation, well below the limit that will char the terrain. Hanson and Robinson (G3)used data from the Nimbus 7 IR monitor to study water vapor and methane in the upper stratosphere. Varansi and Chudamani (G4) studied the intensity measurements in the 720/8cm-’ Q branch of 12C160z. Their measurements differ significantly from previously published data. Harris et al. (G5)made measurements of NOz, HCHO, Hz02,and HC1 in the Northern Hemisphere by mid IR absorption spectroscopy during the 1988 Polarstern expedition using tunable diode lasers. The data was compared to that obtained from less direct methods. Rinsland et al. (G6) studied the long-term trends in the concentration of SF6, CHCIFz, CHC1F2, and COFz from analysis of high-resolution infrared solar occultation spectra. The results were compared with previously reported observations and trends using one-dimensional model calculations. Notholt et al. (G7) determined absolute infrared band intensities and air broadening coefficientsfor the spectroscopic measurements of formic acid in air. Cielo and Cole (GB) evaluated the possibility of usin near-FT-IR to monitor the concentration of oil in water, and discussed possible problems in taking spectral measurements including attenuation b scattering from oil-water interfaces in an emulsion and pcasitle variation in spectral characteristics for different kinds of crude oil. Gonzalez-Davila et al. (G9) used IR and fluorescence spectroscopy to obtain information on the level of dissolved dispersed hydrocarbons in sea water. Montgomery et al. ( IO) reported on the development and use of a continuous N 0 analyzer to study the NzO emissions from a pulverized coal-fired boiler down to a few ppm. N20 levels were found to be substantially lower that levels previously attributed to such sources. Yonebayashi and Hattori (GII)used proton NMR and IR to stud 40 humic acids resent in various types of soils. Paim et al. (J12) c h a r a c t e r J t w o Brazilian topsoils under savanna grassland along with five soil fungal melanins using IR, elemental, and functional group analysis. Hall et al. (GI3) quantitatively measured the combustion products of chlorinated hydrocarbons using FT-IR. Nonlinearities were noted in species having rotational lines narrower that the instrument resolution. Demirgian (GI4) et al. discussed the potential for using FT-IRas a continuous emission monitor for stack gas emitted from municipal waste incineration. Data was presented for the determination of CHCL and CC1, in the Dresence of CH C12, MeC1, and C2Cl 4uazon (GI5) reporte8 on the derivation of formic data recorded durine the 1986 Carbonaceous SDecies Methods Comparison StGdy, including detailed insiantaneous and hourly average values. Mirzoeva et al. (G16) developed a method for the determination of N20 using the absorption band 2ulat about 3.87 pm. The method is reported suitable for determining pollution in laboratory or production plant conditions as well as in the ground layer of the atmosphere. Breton (GI 7) reported on field experiences obtained using the Spectrum 677 IR HClemission monitoring system used to monitor HCl in flue gas. This system is designed for HC1 measurement after gas cleanine svstems. SDartz et al. (G181 oDtimized a FT-IR to identifywan>quantify*volatileo r g d c compounds such as CC14, CClJi’, CHCLF2, CCl2FZ,C12F2, CHCl,, and CH2ClZ.The au-

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thorn report that the field-transportableapparatus can monitor small concentration changes over relatively short periods. Musio (GI9) develo d and used a continuous IR analyzer to perform online N rmeasurements a t nine utility boilers using ulverized cod or oil. Brown (G20) described an IR procefure and the equipment used to determine the concentration of CO, COz, and hydrocarbons in exhaust ases from internal combustion engines. McDaniel et al. (521) determined the IR absorption cross-sections for eight commonly used halogenated methanes and ethanes as a function of temperature from 203 to 293 K. The values obtained were compared to those from previous reports, alon with recommendations for use in atmospheric sensing antradiative energy transfer models. Hussain and Rees (C22) used FT-IR to study the gaseous combustion product of yrotechnic mixtures containing carbon in argon, nitrogen, ana air. Kallonen (G23) used an FT-IR spectrophotometer equip ed with a long path gas cell in to determine CO, COz, connection with the Cone HCN, HC1, SOz, and NOz and acrolein in smoke gases. After careful calibration the precision of the FT-IR analysis was found to be the same as in commercial online gas analyzers. Komhyr et al. (G24)reported on COzmeasurements made during 1974-1985 at Mauna Loa Observatory, Hawaii, using a nondispersive IR analyzer, with emphasis on the measurement methodology. Fertig (GW)reported on an IR analyzer that corrects inaccuracies in the analysis of a fluid caused by molecular collision broadening. The determination of N 0 anesthetic gas in breath analysis was used as an example. Levine et al. (G26) ex lored and re orted on the differences between FT-IR and i t e r infrarei instruments used for monitorin airborne gases and vapors of industrial hygiene concern. horkplace air monitoring applications such as the relative utility of these systems as remote sensors at a hazardous waste site, emissions from a chemical vapor deposition furnace, and C1CH:CClZsamples from a degreasing operation are discussed. Farmer et al. (G27) re orted on the data obtained in measurin stratospheric &l during two Balloon Intercomparison tampaigns and determined that a precision of 10%-15% can be confidently expected. Hunt and Sandridge (G28)describe a lightweight portable gas analyzer which can be used to monitor gaseous pollutants in the atmosphere. Ainsworth et al. (G29) have shown that the analytical method used to determine the amount of silica in dust samples in coal mine atmos heres can be im roved by modifying the procedure to inclufe the use of a F8-IR spectrophotometer. The silica analysis can be performed more precisely and with a substantial savings in time. Pacheco et al. (G30) studied the initial stage of chlorideinduced atmos heric corrosion of iron using adsorption spectroscopy. 8pectra obtained from powdered inner and outer rust samples grown in simulated high C1- conditions under various relative humidity levels show potential for the characterization of Fe oxides and oxyhydroxides forms in the early stages of the rusting process. Kristiansen et al. (G31)Determined the vapor concentration of a mixture of cumene and propanol mixtures in an animal exposure chamber using single-beam infrared spectrophotometry. The method was evaluated in a real toxicological investigation dealing with interactions between two solvents and was found to be valuable. Varanasi and Chudamani (G32) studied the temperature dependence of line shifts, line widths, and line intensities of methane at low temperatures using a tunable diode laser at temperature rang' from 161 to 295 K, using He, Ne, Ar,H2, Nz, Oz, and air as%e perturbers. The temperature dependence of the collision-induced line shift was found to be different from that of the corresponding collision-broadened line width. Collette (G33)developed a method for predicting reactivity parameters of organic chemicals from spectroscopic data to assist in assessing the environmental fate of pollutants. Selected points from the Fourier transforms of mid-IR gas- hase spectra were used to predict the rate constants of the d a l i n e hydrolysis of 41 carboxylic acid esters. Goldman et al. (G34) reported on results obtained from using a new Michelson-type very hi h resolution interferometer spectra of molecules of atmos teric interest. Data was reported for HN03, C10N02, H&NOZ, NOz, and COF2.

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Comparison of the new spectra with line-by-line simulations showed that previous spectral line parameters are often inadequate and that new analysis of hi h-resolution laboratory and atmospheric spectra and improve8 theoretical calculations will be required for many bands. Bechera et al. (G35) developed and used a tunable diode laser to measure and study the chemical behavior of hydroperoxy compounds in the atmosphere. McManus et al. (G36) described the construction of an instrument capable of measuring atmospheric methane. The instrument has the sensitivity to detect fluctuations of about 20 ppb. Herget and Demirgian (G37) used FT-IR and partial least squares to determine the minimum detectable concentration value for eight chlorinated hydrocarbons in a mixture of water, carbon dioxide, and nitrogen. Burrows (G38) reported on the use of FT-IR for compliance monitoring toxic compounds in flue gases and vapors. Small (G39) developed discriminant analysis techniques for the identification of atmospheric pollutants from passive Fourier transform infrared interferograms. Gierczak et al. (G40) evaluated the performance of an FT-IR analyzer for determining the components of dilute vehicle exhaust and reported on the detection limits for 22 compounds. Rieger et al. ((742) used FT-IR spectroscopy along with conventional methods to analyze exhaust ases from vehicles using reformulated gasoline and MeOkgasoline blends. Plummer (G42)reported FT-IR shows great potential for use in emissions monitoring applications. Field studies included continuous monitoring a t a hazardous waste incinerator, a sewage sludge incinerator,and a coal-fired boiler. Howe (G43)et al. reports that an FT-IR analyzer is being installed for the determination of CO, NO, NOz, SOz, CHI, HC1, HF, and NH3, in incinerator flue gas.

(H)FOOD ANALYSIS The agricultural and food industries commonly use infrared spectrosco y, especially the near infrared, in the characterization of tRese products. Berset and Marty (HI) observed the protective effect of various antioxidants on all-trans beta carotene during cooking and storage using reflectance near-IR (NIR) spectroscopy. Yasaei et al. (H2)characterized cholesterol in oils extracted from plant seeds. Reflectance NIR was also used to estimate pectic substances in peaches, apricots, and apples by Polesello et al. (H3). Biphenyl residues in whole citrus fruit were determined from mid-IR spectra by Losada et al. (H4). Available lysine in wheat flour was measured using the rocedure described by Letellier and Cuq (H5). Tge application of infrared spectroscopy to the study of bread stahng and the retro adation of starch was discussed apparatus used to measure the by Wilson et al. ( H 6 H 8 ) . amylopectin content in rice was described by Satake (H9). Self-associationof caffeine in water was studied by Falk and Manuel (HIO). Evans et al. ( H I I ) compared X-ray fluorescence and NIR reflectance data to determine lucosinolate content in rapeseed. Improvements to infrard methodology for d e t e " g fat content of milk were discussed by Biggs and McKenna (HI2). The effect of dietary fat supplements on the IR analysis of milk fat was investi ated by Estridge and Palmquist (HI3). Ustunol et al. (HI47 characterized eight different enzymes used to coagulate pasteurized milk. The partial least squares method of quantitative analysis was used by Carl (HI51for analysis of milk fat. Fat content in a wide variety of foods was measured usin an extraction/infrared procedure developed by Cronin and bcKenzie ( H I 6 ) . Olinger and Griffiths (HI7)used principal components analysis on mid-IR spectra to clasaify various wheat varieties. Phytic acid in cottonseed was determined in the near-IR by Panish et al. (HI8). Kim and Williams (HI91 analyzed starch, protein, and energy in feed rains. Similarly, moisture, prokin, and oil content in cramk seed was measured by Hartwig and Hurburgh (H20)and in maize by Orman and Schumann (H21). The variation of fatty acid spectral assignments in different types of oilseeds was discussed by Panford and DeMan (H22). Fairbrother and Brink (H23) examined carbohydrates in the cell walls of forages. A variety of quality components in clover were determined by Marten et al. (H24) and Astaveit and Marum (H25).Protein levels of various grasslands in Spain were determined by Garcia-Criado and

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Garcia-Cuidad using NIR reflectance spectroscopy (H26).

(I) BIOCHEMICAL APPLICATIONS The study of the photochemistry of biolo ical s stems provides insight into the structure of these compfex moLcules. Infrared spectrosco is often used to characterize the activity e photosystem reaction center isolated of these systems. from pea chloro lasts was characterized by He et al. (11). Leonhard et al. 82)conducted model compound studies on the electrochemical activity of chlorophyll. Bauscher et al. (13,14)recorded infrared spectra of model quinones used as electron acceptors in photosynthetic reaction centers. The primary quinone environment in photosynthetic bacterial Hayashi reaction centers was studied by Breton et al. (15,161, et al. (17),Berthomieu et al. (181,Nabedryk et al. (191,Bagley et al. (IlO),Thibodeau et al. (111)and Maentele et al. (112). Infrared spectra of photooxidized spinach pigments by Chapados et al. (113,114)provided information about configuration of proteins during bleaching. Klughammer and Schrieber (115) used the near-IR re ion to study photooxidation in spinach chloroplasts. Red-tght irradiation of pea h ochrome was monitored with infrared spectroscop by sa& et al. (116)in order to provide information acout structural changes during hototransformation. Nabedryk et al. (117,118)found no evixence for enolization of chlorophyll a after photooxidation. Infrared spectra of the red and far-IR absorbing forms of oat phytochrome were measured and analyzed by Siebert et al. (119). Infrared spectroscopy has become an important tool in the analysis of lipids and membranes in biochemical materials. Wu et al. (120)monitored secondary structural changes associated with binding of bovine prothrombin to acidic lipid membranes. Choi et al. (121)showed that the presence of cholesterol does not alter the nature of binding of calcium ion to phosphatidylserine. PRODAN, an environmentally sensitive fluorescent probe, was used to study the effects of hydrostatic pressure on lipid bilayer in work by Chong et al. (122).Binding of terbium and calcium to phosphatidylcholine was studied by infrared, NMR and optical spectroscopies by Petersheim et al. (123).Goormaghtigh et al. (124)evaluated the secondary structure of apo B-100 rotein in human low density lip0 rotein. Ethanol-induce{ changes in rat liver plasma memtrane were evaluated by Lewis et al. (125).Auger et al. (126)performed high pressure studies of phosphatidylserine bilayers, analyzing their interactions with the local anesthetic tetracaine. The solvation of bilirubin in lipid bilayers under high preeaure was characterized by Zakim et al. (127).S ntaneous vesiculation in lamellar phospholipids was s t u d i s y Hauser et al. (128). Stewart et al. (129)characterized hydrogen bondin in diphytany lycerol phospholipids. Self-association in bileki ids was stu led by Antonian et al. (130).Physiochemic properties of human er hrocyte membranes were studied by Fiorini et al. (131). enteno and OLeary (132) examined the interactions of short-chain alcohols with dimyristoylphosphatidylethanolaminebilayers. Brandenberg and Seydel (133)investigated the phase behavior of lipopolysaccharides in Gram-negative bacteria. Subgel phases of a series of saturated straighbchain diacyl hosphatidylcholines were studied by Lewis and McElhaney 834).The secondary structure of the membrane-binding domain of rat liver cytochrome b5 was discussed by Holloway and Buchheit (135). The structural and thermodynamic behaviors of lipids in the vicinity of acet lcholine receptors was observed by Bhushnan and M c d m e e (136). Walde and Luisi (137) measured the hydrolytic activity of lipolytic enzymes in reverse micelles by following water consumption during the reaction. The effect of cholesterol on the location of organic molecules in lipid bilayers was studied by Mu a and Casal (138).Polarized IR s ctroscopy was used to dietermine the secondary structure of%ptheria toxin in experiments by Cabiaux et al. (139). The secondary structure of GALA, a synthetic peptide designed to mimic the behavior of viral fusion proteins, was examined by Goormaghtigh et al. (140).Muga et al. (141) monitored the interaction of apocytochrome c with phospholi id membranes. The liquid crystalline phases of dioleoylpRosphatidylcholine and monooleoylglycerolwere studied by Nilsson et al. (142). Castresana et al. (143)examined deuterated fatty-acyl

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methyl groups in phosphatidylcholine liposomes. The secondary structure of proteins and orientation of protein domains in li id bilayers were investi ated by Goormaghtigh et al. (144).&ructures of orcine an8 bovine pancreatic phospholipase were analyzefby Kennedy et al. (145). Structural changes upon membrane bin of colicin E l to li id vesicles were discussed by Suga et al. ( 46). The role of rocking modes in the uantitation of conformational disorder in phospholipid blayers was investi ated by Mendelsohn and Davies (147).Attenuated total reiectance spectroscopy and its role in the study of biological membranes was discussed by Braiman and Wilson (148). A procedure to assay membrane lipids immobilized to silica was outlined by Markovich et al. (149). Characterization of the structure of proteins is often erformed by infrared spectroscopy. Strand and Jakobsen (f50) reported on the use of this technique to study proteins in solution, while Okada et al. (151)used the IR microscope to obtain spectra of roteins in the solid state. Halverson et al. (152)investigatefthe 0 sheet structure in amyloid-forming peptides. Time-dependent changes in human hair keratin under oscillatory strain were monitored in ex eriments by Dowrey et al. (153).Moss et al. (154)develope! a technique which combines infrared spectroscopy and electrochemistry to study redox-linked conformational changes in proteins. Fuller and Singh (155)explored sampling techniques for the analysis of secondary structures of tetanus neurotoxin. A near infrared probe was used by Antoine et al. (156)to determine the hydrophobicity of serum albumins. The production of recombinant proteins in E. coli was monitored by Wong et al. (157). Prestrelski et al. (158)discussed the influence of metal ion binding on the secondary structure of bovine lactalbumin. Taraszka et al. (159)identified structural markers in order to study transport and reaction mechanisms involved in vitamin B1 protein interactions. LeGal and Manfait (160) performe in vivo studies monitoring binding of free fatty acids to human serum albumin in test subjects before and after running a marathon race. The effect of formaldehyde fmtion on the secondary structure of bovine serum albumin was investigated by Mason and O’Leary (161).A data base of protein infrared spectra was used to determine the secondary structure of these materials in a study by Sarver and Krue er (162).Andrews-Willberforceand Patonay (163)used near-b spedroscopy to study binding sites on albumins. Chemometic techniques were used to determine protein structure in the experiments of Lee et al. (164)and Douweau and Pezolet (16). Derivative spectroscopy was used by Dong et al. (166)to probe the secondary structures of globular proteins in water. Detergent-solubilized uncouplin protein from brown adipose tissue mitochondria was anafiyzed in studies by Rial et al. (167).Li et al. (168)observed the influence of metal ions on the secondary structure of albumin. Core protein from pig skin proteodermatan sulfate was investigated by Renugopalakrishnan et al. (169). Drosophila chorion roteins were changes studied by Hamodrakas et al. (170).Pressure in!uced in the secondary structures of E. coli methionine repressor protein and in poly(L4ysine) were measured by Wong and Mantsch (171)and Carrier et al. (172).Ionization states of the 5’-phosphate group in several coenzyme forms of mitochondrial aspartate aminotransferase were evaluated by Sanchez-Ruiz et al. (173).Alterations in the chemical structure of horseradish eroxidase were investigated by Arseguel et al. (174).Modit!cations of creatine kinase were evaluated in the studies of Lin et al. (175).The temperature dependence of the spectra of ribonucleaseA and troponin C was monitored in the experiments of Yamamoto et al. (176). An evaluation of the catalytic activity of a thiazolium salt polymer as a model for thiamin pyrophos hate activity was conducted by Yamashita et al. (177).Cargon-13 labelin of amino acid residues was used to examine protein seconfary structure in studies of Tadesse et al. (178).The helical conformation of double stranded oligoribonucleotides was characterized by Liquier et al. (179). Kulinska et al. (180)investigated cytidine and deoxycytidine nucleosides in a ueous media. Tajmir-Riahi (181)studied the interaction of 8eoxyguanylic acid with alkaline earth metal ions. The structure of a fr ent of colicin E l was characterized by Rath et al. (182). hydrogen bond’ of uracils with water in an argon matrix was investigated by?raindourze et al. (183).Similarly,

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spectra of matrix isolated cytosines were presented by Jaworski et al. (184).Theoretical calculations and matrix IR spectra of isocytosinewere compared by Stepanyan et al. (1&5), for adenines by Wiorkiewicz-Kuczeraand Karplus (1861,and for thiouracils by Rostkowska et al. (187). Resolution enhancement techniques were used in studies by Kennedy et al. (188)to probe the secondary structures of helical and ribbon-type pe tides. Similar s ectral enhancement techniques were use! by Dev and WJters to help understand protein-DNA interactions (189). Immunological properties of bovine phospholipase A2 were related to structural properties in a series of experiments by Osthoff and Ne1 (190). The effect of pH on the structure of 8-h drox 2’ deoxyyosine was investigated by Culp et al. (191r Jac&oi et al. 192)studied the effect of pH on conformational transitions in pol (L 1 he). Spectra of nanomolar concentrations of immunog&b;g G were obtained using attenuated total reflectance spectroscopy by Singh and Fuller (193).The effect of a propeller-twist structure in a homo olymer DNA on the far-IR region of the spectrum was calcJated by Young et al. (194). Structural characterizations of trypsin and chymotrypsin were conducted by several authors. Mateus Ventura (195) used enhanced resolution techniques to study spectra of soybean trypsin inhibitor. Reactive center cleavage during expression of inhibitory activity in q-antit sin was mvesti ated by Haris et al. (196). White et al.797) used (3-13 la%elingto study the structure of the reaction intermediates trans-cmamoyl and hydrocinnamoyl-a-chymotrypsin as well as the 8-phenylpropionyl derivatives of chymotrypsin (198). These authors also investigated the role of hydro en bonding in enzyme catalysis for acylchymotrypsins (1997. Barth et al. (1100)investigated ligand binding and conformational changes in the calcium ATPase of sarcoplasmic es in the secondary structure reticulum during catalysis. C of sarcoplasmic reticulum AT ase on controlled protein cleavage were monitored by Tereul et al. (1101). The effect of pressure on this system was monitored by Buchet et al. (1102).The effect of solubilization of sarcoplasmic reticulum membranes by sodium dodecylsulfate was measured by Prado et al. (1103). Polysaccharide characterization was often performed using infrared spectroscopy. Fairbrother et al. (1104)described a uantitative procedure for monitorin lactose and lactic acid juring whey fermentation. The near-& was used to determine hysiological levels of glucose in an aqueous matrix in studies y Arnold et al. (1105). Conformational structure of iduronate saccharide residues in gl cosaminoglycans was investigated by Grant et al. (1106). olecular structure, ordering, and interactions in Langmuir-Blodgett films of glucose oxidase were observed by Ancelin et al. (1107). The sulfate composition in glycosaminoglycanswas determined by Longas and Breitweiser (1108). Infrared s ectroscopic studies rovide the basis for much research ine!t chemistry of the rfodopsin-related materials. Rothschild et al. (1109)discussed, in general, the infrared spectra of rhodopsin and bacteriorhodopsin. The photoreaction of rhodopsin with 11-cis-13-demethylretinalwas investigated by Ganter et al. (1109).Light-induced changes in the structure of bacteriorhodopsin were studied by Gerwert et al. (1110). Polarization studies were used by Earnest et al. (1111)to characterize the secondary structure of bacteriorhodopsin. Protonation in thismolecule was studied by Ormos (1112).The N intermediate of bacteriorhodopsin was characterized by Pfefferle et al. (11!3). The proton p p p i n mechanism and the role of aspartic acid 212 were mvestigatej by Rothschild et al. (1114).Fahmy et al. (1115) compared theory and experiment to explore the mechanism of photoisomerization in bacteriorhodopsin (1116).Retinochrome and its primary photoproduct, lumiretinochrome, were characterized in the work of Sekiya et al. (I117). The hotochemistry of deionized urple membrane was studied y! Fahmy and Siebert (I1187. Blood chemistr is often investigated using near infrared spectroscopy. Scdwer (1119)described a devlce used for the noninvasive measurement of blood analytes, especially blood glucose. A near-IR based instrument used to monitor blood oxy enation in human newborns was discussed by Tamura et a! (1120)and by Oda et al. (1121).Ferrari et al. (1122) determined oxygen saturation of cerebral venous hemoglobin

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in a noninvasive procedure. The oxygenation level of myoglobin and hemoglobin in the cardiac muscle in vivo was measured by Thorniley et al. (1123).Sheppard et al. (1124) described a device for measuring hemoglobin and oxygen content in whole blood. Cerebral transit time and the relationships between oxyand deoxyhemoglobin were monitored in hypotensive dogs by Ferrari et al. (1125).Thorniley et al. (1126)performed an in vivo study of the dissociation kinetics of oxygen from oxyhemoglobin in rat brain. The effect of pH on the tertiary structure of aqueous solutions of oxyhemoglobin was investigated by El Antri et al. (1127).Conformationalanalysis using near-IR s ectra in hemoglobin and iron-manganese h brids suggestexa model for heme-pocket geometry in stu2es by Chavez et al. (1128). Curve-fitting techniques were used by Abbott et al. (1129)to indicate the A and El amide carbonyl vibrations in hemoglobin. Barbucci et al. (1130)used attenuated total reflectance spectroscopy to study antigenlantibody recognition, specifi d l y for the biotin-avidin complex. The secondary structures of human class I and 11MHC antigens were characterized by Gor a et al. (1131).Singh et al. (1132)investigated the molecufar structure of tetanus neurotoxin, Surewicz et al. (1133) studied the structure of cholera toxin and Singh et al. (1134) analyzed the structure of botulinum neurotoxin in aqueous media Griebel et al. (1135)explored the role of mitochondrial redox levels and the resence of E. coli bacteria in primate muscle and brain. gaentele et al. (1136)discussed spectra of pigments and redox com onents in the bacterial reaction center. Classification and igntification schemes for bacterial analysis based on IR spectra were presented by Helm et al. (1137). The chemistry of the formation of gallstones may be studied by infrared spectroscopy. The effect of environmental influence on the frequency of the PO - moiety in biomolecules was discussed by Pohle (1138). Cafcium ion binding to bilirubin was studied by Wu et al. (1139)and by Soloway et al. (1140). Protein and hydroxyapatite content in guinea pig and human gallstones was compared by Xu et al. (1141).Hesse et al. (1142)developed a procedure for interpretation of the spectra of urinary stones. The secondary structure of two recombinant human growth factors was characterized by Prestrelski et al. (1143).Infrared s ectra of microtomed sections of human colon tissues were ottained by Wong et al. (1144).Benedetti et al. (1145)used the IR microscope to study human solid tumor cells. Highpreasure FT-IR spectroscopy was used to monitor the alteraton of hepatic li ids and proteina in rats with alcoholic liver disease in a s t u d y i y Takahashi et al. (1146). Foley et al. (1147) measured the res onse of the Datex Ca nomac to exhaled alcohol. Rey et af(1148,1149)examinexthe carbonate and phosphate environments in bone material. Braue et al. (1150) used attenuated total reflectance spectroscopy to evaluate topical protectants. The pharmaceutical industry uses infrared spectroscopy for drug evaluation. Firth (1151) reported on the identification of street druga by infrared spectroscopy. S ectra of sulfa drug molecules were presented by Jigeesh et al. t152). A procedure for the determination of benzodiazepine in binary mixtures of oxazepam, medazepam and diazepam was outlined by De Julian-Ortiz and De La Guardia (1153).Braue and Pannella (1154,1155) discussed a procedure to monitor drug retention during animal inhalation exposure. SURFACE TECHNIQUES AND APPLICATIONS (J) TECHNIQUES AND APPLICATIONS OF IR REFLECTION SPECTROSCOPY Gigola and Haller have developed a diamond internal reflection cell for making IR spectroscopic measurements on metal and metal oxide films (51).McEwen, Drumm, and Smith reported on a new sample clamp and prism holder which improves the quantitative internal reflection IR spectroscopy of paint surfaces by increasing the contact between the paint samples and prism surfaces (52).Stole and Porter have constructed an im roved sample holder for IR external reflection spectroscopy 63). Harrick and Milosevic described a refractive grazing incidence external reflection IR spectrometer attachment (54). Khoo and Ishida have described a metal overlayer FT-IRATR technique that was found to substantially enhance the

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si al-to-noise ratio of spectra monolayer and submonolayer fi& (J5). The metals used in the latter were Au and Al. Using thin films of Si on a Cu substrate Finke and Schrader demonstrated an increase in sensitivity of reflection-absorption IR spectroscopy for examining thin layers of poly(meth 1 methacrylate) (J6). Xu and Yates described a new FTIL reflection-absor tion spectrometer and a background subtraction methozto be used to study adsorbates on single crystal surfaces (J7).Their ap atus and method is supposed to cancel absorptions due to ackground atmospheric gases and compensate long-term baseline drifts. A novel method for measuring both diffuse and absolute IR reflectance employing an integrating sphere was discussed by She ard (J8). Forrister and Starr designed a parabolic mirror Eased directional reflectance accessory for use with an FTIR s ectrometer to measure directional reflectance of texturelsurfaces (J9). Meuse and Tomellini (J10)and Heinrich et al. (J11)have develo d a technique for determination of or anic compounds y IR/ATR which uses a polymer-coatef internal reflection element. The substance of interest absorbs into the polymer film from either gas or li uid matrices and is detected in the ATR spectrum. A rgated technique, reported by Ruddy and McCabe, used Teflon-clad fluoride $lass optical fibers to detect propane (J12). The propane is detected by IR-ATR when the gas diffuses into the Teflon cladding of the fiber. Kretschmann ATR-IR spectroscopy for the investigation of metal/liquid or solid interfaces was discussed by Hatta et al. (J13). This method involves the enhancement of the electric field at the surface of a thin metal film caused by the collective resonance of free electrons under the influence of incident IR light. They suggest this technique will allow the measurement of IR spectra of species in situ on metal surfaces without interference from signals of bulk species. Effecta of the polarization of the incident light on the rei ion flection-absorption IR spectra of an ultrathm organic f a metalized slide was described by Song and co-workers (514). They SWJ eat that to avoid spectral distortion, ppolarized light should ways be used. Sperline has also investigated the effect of polarization on the analytical accuracy of ATR (J15) and gives a method for determining the wavelength-dependent polarization ratio for any spectrometer. Ribbing and Hjort have demonstrated an empirical relationship between the long wavelength edge of the residual ray band in IR-reflectance and Young's modulus, the melting point and to indentation hardness (J16). The materials studied were partly ionic compounds including alkali halides, semiconductors, and some hard compounds. Brown and Smith compared and interpreted the high resolution reflection s ectra from 5 to 20 pm from selected optical black coatings 817). They found a surprisin number of stron sharp features in the spectra. Guida et a! studied the AT&IR s ectra from principle faces of crystals of the strongly absorrJ ing anisotropic com ound orthorhombic disodium ntacyanonitrile dihydrate PNa [Fe(CN)bNO].2H20) (J18).Z e y compared the experimendy d e t e m e d spectra to ATR spectra calculated from a Kramer's-Kronig analysis of external reflectance data and compared these both to powder ATR data and polarized transmittance spectra of single crystals of the same compound. Samanta and co-workers demonstrated the use of polarized ATR-IR to study fiber structure (J19).They showed chain conformation and crystallite orientation chan es which occur as a function of draw ratio in agreement with t r a y diffraction data. Several groups have demonstrated ATR-IR aa a noninvasive method for in vivo as well as in vitro measurements in biological analyaea and diagncwes. ATR-IR has been used by Mak et al. to examine the kinetics, extent, and mechanism of percutaneous drug absorption in vivo in humans (J20). They used 4-cyanophenol as a model permeant and showed the enhancement of absorption when delivered in solutions of propylene 1 col and oleic acid. Baraga and co-workers have applied A'f6-m to the characterization of atherosclerotic lesions (J21).This technique was suggested as a possible in vivo method of monitoring lesions as well as a way to probe the molecular details of atherosclerosis and other human diseases. The analysis of blood constituents such as glucose and urea was discussed by Kruse-Jarres et al. (J22).Bean et al. demonstrated the ability of ATR-IR techniques to

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(K) SUPERCONDUCTORS AND THIN FILMS IR spectroscopy has been widely applied to advance the u n d e r s t a n y of high temperature superconductivity and the chemical an electronic structure of high temperature superconductors. Timusk, Porter, and Tanner observed structure in the IR reflectance s e a of the high temperature superconductor YBa2Cu307which they attributed to an electron-phonon interaction (K1).Geserich et al. pointed out the similarity of the optical reflection spectra (0.2-6.0 eV) and electron energy loss spectra (EELS) of YBa2C~306.8 superconductors and NiO and discussed the interpretation of the spectra in terms of charge transfer models of superconductivity (K2).Ziaei and co-workers measured the far-IR reflectivity (20-1000 cm-') of YBa2Cu408over a tem erature range of 20-300 K and identified six phonon mofes due to lattice vibrations of B1, symmetry and two superconducting energy gaps at ca. 150 cm-' in the c direction and at ca. 450 cm-' in ihe ab plane (K3). Measured far-IR reflectivities bv Burlakov et al. of Dohcrystalline YBa Cu30, ( x = 6.3, 6.7, 6.9, and 7.0) showed-a decrease in reAectiwty over the entire measured range (50-1200 cm-') proportional to the increase in 0 deficiency (K4).A band at 640 cm-' was attributed to 0 vacancies. In another paper Burkolov et al. +amwed free carrier localization effects on measured IR reflection spectra of YBa Cu30 and YBazCu30s.6at various tem eratures (K5)."he DXIFT spectra of polished sinterec r pellets of YBa2Cu307, and La2- SrrCu304- and related superconducting and nonsuperconducting oxiaes between 500-5000 cm-' were measured at room temperature by Rosenberg et al. (K6). The polarized mid- and far-IR reflectance spectroscopy of was single c stals of YBa2Cu O6 and Bi2SrpCaCu measureTby Abel et al. ( K h . "he reflectiwty of t i e former compound at low temperature indicated an anisotropic energy gap, which, according to the authors, proves the hypothesis of two dimensional superconductivity in this compound. Bazhenov and Timofeev also studied the anisotropy of yttrium barium copper oxide sin le crystals with polarized IR reflectivity between 50 ant5500 cm-' (K8).Bazhenov, Gorbunov, and Timofeev examined the reflectivity spectra from the basal plane of tetragonal YBa2Cu306+,sin le crystals with The temorthorhombic inclusions from 50-1500 cm-' k9). erature dependence of the spectra and the behavior of the tter after annealing allowed the assignment of a feature in the reflectivity to a manifestation of a superconducting gap with 2A = 3.2kT, Geaerich and co-workersreported polarized reflectivi spectra between 5 meV and 6 eV for orthorhombic YBa Cu and tetragonal YBa2Cu30eat room tem erature (K16.%he components of the dielectric tensor Jong the principle crystal axes were determined from a Kramer'sKronig analysis and by fitting a Lorentz-Drude model. A study of YBa2Cu307cryetals by Koch et al. lead to assi (KI1). of a superconductinggap of 1.4kTcfor this compoundgnment Ose et al. have reported the infrared .s ectral properties of an oriented yttrium barium copper ox& thin film on MgO (K12).The dynamical conductivity and absorptivity of YBa2Cu307-thin f i i were determined from IR reflectivity by Renk and co-workers (K13).These authors attributed the far-IR properties to absorption by free carriers that condense below T,, a temperature independent absorption with threshold at 400 cm-'and an absorption at low frequency that may be due to normal conducting carriers. Herr et al. disc d the interpretation of yttrium barium copper oxide films in terms of Mattis-Bardeencalculations (K14).They contend that the latter apply to the anomolous skin effect or the dirty limit regimes, neither of which apply to high temperature superconductors. They believe features in the reflectivity spectra which previously were identified aa the gap are present in spectra of both the normal and superconductingstate, but are obscured by the free carrier absorption above T,. The far-IR transmittance and reflectivity spectra of oriented yttrium barium cop er oxide films were studied by Gao and co-workers (K15).#he films were grown on MgO by pulsed laser ablation and were highly oriented in the ab plane. No su erconducting gap was observed in the spectra. k y k et al. studied IR thin f i itransmission spectra and reflectivity spectra from single crystals of Bi&3r2CaCu208which

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has T , of 85 K (K16).The authors determined that the low-frequenc responses of both materials could be described by a Drude atsorption with a carrier relaxation rate near 100 cm-'. A temperatureindependent absorption at 300 cm-' was observed, but no superconducting gap was evident. Calvani et al. measured IR reflectivity s ectra of bismuth strontium calcium copper oxide superconiuctor films of varying stoichiometry of Ca, Cu, and 0 at 300 and 25 K from 400 to 2000 cm-' (K17).The IR optical functions derived from the data showed a dependence on T The data was discussed in relation to existing models. The vibrational structure in the IR reflectance spectra of pressed ceramic pellets of BizSrzCaCuz08,a high-temperature su erconductor with T, = 85 K was studied by Kamaras et al. k18). Spectra were measured at several temperatures above and below T, and corrected for diffuse scattering and the electronic absorption induced background in the IR region. The temperature dependence of the vibrational spectra exhibited no features attributable to coupling with the electronic system. Polarized IR reflectance of single crystals of bismuth strontium calcium copper oxide performed b Kim and coworkers showed a lar e anisotropy with metalic behavior in plane and insulator-li!e behavior for c-axis reflectance (K19). Watanabe et al. measured IR reflectivity spectra of single crystals of Bi M Co,O for M = Ca, Sr, Ba and m = 1 , 2 as well as bid^&&,^ ana Bi$3r2h4n06.25,which are isotropic to bismuth cop r based high temperature superconductors (K20). A broageabsorption band, near 0.5 eV, was detected for all these materials whether or not they were high T, suerconductors. Humlicek et al. reported reflectance and el[psometric spectra for single crystals of BizSr CaCuzOs superconductors between 0.4-5.3 eV and compared these results to EELS data (K21). Tian et al. presented evidence for electron- honon couphg in the Bi(Pb)SrCaCu oxides, 2212 (T, = 86 and 2223 ( T , = 104 K)(K22). They found two broad peaks at 150 and 450 cm-' in the ratio of the reflectivities in the superconductin state to that in the normal state. Zhong,Cai, and Tang (K237 and Zhong and a larger group of co-workers (K24) have reported the room temperature IR transmission and far-IR diffuse reflectance s ectra of Pb-doped bismuth strontium calcium copper oxi e superconductors and nonsuperconducting samples. 'Totally different" features were found in the su erconductor and nonsuperconductor spectra. Etchegoin, fainstein, and Massa studied the effect of a dc current on the near normal IR reflectivity spectra of BizSrzCal(CU1-x,Mx)208+y with M = Fe and Mn and 1: =