Polyelectrolyte Solutions. A Theoretical Introduction. - Journal of the

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July 5 , 19G2

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A solution of the purple substance exhibits a simple infrared spectrum with a broad band from 8.5 t o 11.O p possessing two poorly resolved peaks at 9.4 and 9.95 p , respectively. One other weak band centered a t 13.05p i s observed. Dodecaboron undecachloride, B12Clll, is a deep red crystalline solid which sublimes in vac’io a t 100’ and melts with little apparent decomposition at 115 l o . The formula was established by elemental analysis: Anal. Found with a 99.1% material balance: B, 24.7; C1, 74.1;CIIB, 0.918; calculated for BI2Clll: B, 24.9; C1, 75.1; CIIB, 0.916, and by molecular weight determinations using the isopiestic method. Found: 523 i- 12; calculated for Bl2Cll1: 520.1. In cyclopentane the red subchloride exhibits a single broad paramagnetic resonance a t a g value of 2.011 with a breadth of 25 gauss between points of extreme slope. Unlike the purple subchloride, no hyperfine splittings could be observed in this case although various attempts were made using the spectrometer a t high resolution with the probe a t low temperatures. The infrared spectrum of a similar solution exhibited a band from S.75 to 10.7 p with a peak a t 9.85 p. A sharp peak a t 11.02 p also was observed. The latter is a characteristic absorption of the BC12group in B2Cl4.? The red subchloride, BI&lI1, absorbs in the visible and ultraviolet regions of the spectrum with a broad strong band centered a t 420 mp and a weak band a t 310 m p . The strong infrared band in the region of 9.3 to 10.0 p common to both of the new radical species appears to be characteristic of boron cage structures since similar absorptions have been reported for BloHlo=,B I ~ H ~ sB1oCll~= -,~ and B12C112-.4

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( 2 ) A I J . Linevsky. 1: R . Shull, 1). I?, l l a n n and ‘I. b‘artik, J . A n t . C h e i i i . .Sot,, 75, 3287 ( I W j ) ,

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We also have observed a similar band in the case of the simpler boron cage in B4C14. Acidic hydrolysis of Bl2Clll occurs slowly even a t 80’ with the reaction virtually ceasing when 9.5 moles of hydrogen have been evolved per mole of initial BI2CII1. In basic solution hydrolysis proceeds according to the equation 2B12Clii

+ 11 OH-

3H2

+ 4BOz- + 2BiaC18(0H)2- + 2Hn0 + 6C1-

Ions similar to Bloc&(OH)2- already have been rep~rted.~ Potassium and tetramethylammonium salts can be precipitated from the alkaline hydrolysis solution. The infrared spectra of these indicate retention of the cage structures. Treatment of BI2Cll1in cyclopentane with an excess of trimethylamine results in a complete discharge of the red color with the formation of the 2 : 1 complex, [ B I ~ C I ~ ~ . ~ N ( C In H ~this )~]~. case also an infrared spectrum characteristic of cage compounds is obtained. The new radical species are unusual in that the boron cage resonance forms probably contribute to their stability. Further characterization of the purple species is being undertaken. Similarly. an investigation of the clear yellow crystalline solid is underway since in many of its reactions free radicals of limited stability can be observed. (:3) 11.F. Hawthorne and A. R. Pitochelli, J . A m . Chenr. Sol-., 82, 3328 (19ti0). (1) E. L . Muetterties. R E. Merrifield, H. C. Miller, W. H. Knoth and J. R. Downing. private communication. (.5) A’. H. Knoth, H . C. Miller, 1). C England, G. W . Parshall and E . I,. hluetterties. J . A m . Chsm. Soc., 84, 1036 (1962).

DEPARTMEST OF CHEMISTRY I’URDUEUNIVERSITY G R A N TLRRV LAFAYETTE, ISDIASA EUGENE P. SCHRAM DEPARTMENT O F CHEXISTRY L~ASHISGTOS USIVERSITV ST. LOUIS,MISSOCRI S.I. ~VEISSMAS RECEIVED M A Y2, 1962

BOOK R E V I E W S Polyelectrolyte Solutions. A Theoretical Introduction. By STUART .A. RICE,University of Chicago, and MIrsvRr! SAGASA~YA, Sagoya University. With a contribution h y H E R B E R MnRAn’ErZ, T Polytechnic Institute of Brooklyn. .Icadeinic Press Inc., 11 1 Fifth Avenue, S e w Ynrk 3, S. \ 7 . 1961. sv 568 pp. 10 X 23.5 ern. Price, .g,16.50. Polyelectrolytes have, duriug the last decade or so, become one o f the most active and fruitful fields of research in physical chemistry, as a consequence of advances in two superficially unrelated fields, synthetic polymers and biochemistry. Pioneer work by Kern, A . Katchalsky and Fuoss on synthetic polymers which were designed to be simultaneously polymers and electrolytes gradually built u p a store of descriptive information about these hybrid substances, from which a qualitatively useful molecular model was deduced. The polyelectrolytic nature of many biochemical substances was then recognized, and naturally occurring compounds such a s nucleic acids atid proteins began t o be investigated as polyelectrolytes. Furtherniore,

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E. Kachalski, Doty and others comnienced the deliberate synthesis of polyelectrolytes which were designed to be chemical a s me11 as electrochemical models of natural substances. Meantime, attempts were made t o construct a theory which i5ould correlate the observed nlacroscopic properties of polyelectrolytes with molecular parameters. The difficulty the theoretician faced was in the working model to use as his starting point: if it were made simple enough t o be amenable t o mathematical treatment, i t departed too far from reality; if i t were made elaborate enough t o realistically describe all the details of behavior which one would like t o account for, i t became too complicated for mathematical analysis. Rice and Sagasawa have summarized in this first book to appear 011 polyelectrolytes the various theoretical approaches to the problem, together with sufficient experimental examples to show how far the theory in its present state of development can go in accounting for observation>. T h e development is presented in logical sequence, so t h a t :I graduate student with a firm background of thermotly-

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iiainics, statistical mechanics atid advanced calculus can follow the arguments, and use the book as a n introduction to research in polyelectrolytes, which was the authors’ stated purpose for the book. Considering the intended reader, the book begins with a review of the statistical mechanical treatment ( i f general solutions aiid of the equilibrium properties of simple electrolytes before proceeding t o polyelectrolvtes. Then rigid polyelectrolytes (exemplified by marly ihorgaiiic colloids) are treated. In Chapter 5 ( b y Morawetz), the goal is finally reached: the flexible charged polymer is brought on stage, arid becomes the center of interest froin there on. Chapters 6 and 7 present the current theory o f polyelectrolytes, much of the material based mi work of oue of the authors. The last four chapters then apply the theoretical treatment to reversible and dissipative processes in sdutions of polyelectrolytes; these are the chapters which will be especially useful both to the graduate student a n d a l s ~to the experienced researcher in biochetnistrj. ~ v l i orealizes the necessity of considering most of the substances with which he works iis both natural products ( r f biochemical importance and as iiieinbers of a special category uf compounds for which the theoretical chemist aud the physical chemist ha\-e established a general pattern o f properties and behavior. Finally, the book is recorninended to the research worker in polyelectrolytes as a cotivenient anti well organized reference source for much of the material which previously r ~ i only s available in a multitude of articles scattered through many journals in the lihnirj., or mauy reprints in his files.

the material could be iuaiiaged b ~ students . not previously exposed t o formal physical chemistry beyond the elementary level. There is some question in this reviewer’s mind whether this aim has indeed been achieved. X iiumber of his theoretical treatments, particularly those dealing with denaturation, arid with the hydrodynamic and elastic properties of proteins a i d protein fibers do require, if not f i rrtrial background in physical biochemistry, at least some of the sophistication t h a t onll- a particular variety of protein chemist is likely to ha\-e. 011 the other hand, bright students with a natural talent for physical chemistry aud inathematics should find the subject matter straight forxird and provocative. The title of the vcriunie, “Protein Structure,” i i , iu I I I J opinion, slightly misleading since what is presented is a discussion of proteiris as visualized iind studied by the authiir and his colleagues. Scheraga has been intimately involved, esperiinentally and theoreticall)., with all of the subjects he discusses in his book. His competency in the physical aspects i u f protein chemistry makes it possible for him to write with authority. The theoretical approach taken, however, riccasionally involves assuniptims t h a t wciuld not be universallj- accepted by all experts in the field. For esarnple, :ilthough it is clear from the ivork of Kendrew a n d hi\ colleagues that a variety of iicin-covalent interactivns call iind do exist in a globular protein (myoglobinj, it is perhaps premature to develop sets of tlierincidl-n~irnicequations governing some o f these interactions before their presence in the proteins uiider ccriisideration has been deinirnstrdted in a n unequivocal fashioii. However, even these sections S T E R I . I S G CHEMISTRY L.4BOKATOK\. o f the book serve a b ;i useful didactic treatment for students Y A L E UNIVERSITY l~w h o wish to become thorH. v. HIRSCHHAUSES.\-erlag Chemie, G.tii.b.H., oughly falni~iarwith one ( i f the active approaches t o the Pappelallee 3, ~ ~ e i n h e i i i i j B e r g s t r .Germany. , 1961. subject. 1 207 pp. 14.5 X 21.5 cui. Price, D X . 28.--. S A T I o S A L HEAK-r I S S T I T U T E CfIKISTIAS B. . \ S F I S This book is a trauslatioii iiito German of a bgok iii Freucli LARORABORT O F CEI,LL-I,AR ~ ’ f < Y S X O L O G Y by the same author, entitled “Les Spectres Electroniques BETHESDA 11, MARYLASD en Chirnie T h h r i q u e ” (Paris, fiditions de la Revue d’opti-. que t h h i q u e et instruinentale, 1959). hdded in this editicm have been a number of exainplcs, a few new references, Gas Chromatography. By L). .\SIBROSE, Pli,L)., F . K . I . C . , and a useful listing o f quantuiii-tIiecJretica1 calculations by arid BARBARAX. XmmcxE, R.Sc. George Newties inolecule and method. Limited, Tower House, Southariiptirii Street, Londotl, The inain topic discussed is the quantum theury of the \ Y . C 2, England. 1961. vii 220 pp. 14 X 22 cui. visible and ultraviolet spectra of organic molecules. Tlic Price, 40s. :tuthor wanted not so much t o cover the literature in this field as to introduce his readers t o i t by working througli Several >-cars agu, an>-ouc could learii all tlicrc \\as tii illustrations of the various methods. H e well presents iii know about gas chromatography by recrding ii ilaridful i i f this way the valence bond method, the simple molecular papers. S[I\I-, with over cine thousand papers appeariiig orbital method, the method of antisyrrinietrized products of annually, it is impossible eveu t o read t h e titles o f thein a l l . inolecular orbitals (erroneously called the inetlicid of antii t is clear that :t chemist \vishing to use tliii technique iiisyrninetric niolecular orbitals j, and the methud of free electelligciitl>- iieeds R crimpact s ~ u r c eof inforrnation oil the trons, as these methods were practiced in about 1960. Actheory, practice a n d present state OF the a r t . .liiilmise cording t o the reviewer’s count, the more thari 300 references fills the iieetl for a wide survey rvhich will eiiable the techcited fall as follow. year bl- year, beginning with 1930: nologist t(J construct ail apparatus antl use it wisely. ’Thc 1 , 6 , 4 , 1 3 . 9 , 9 , 9 , 9 . 8 , 14,6, 5 , l l , O , 4 , * 5 , 8 , 1 9 , 1 8 . 3 0 , 2 ” , hook provides a basic introductioti hut does not attenipt 17, 11, 12, 4, 18, 6, 1, 4 , 4 , 4, 1. The recent book I]>. to carry tlirougli to the fine puints of theory ivhich arc iii LIaudel, Lefebvre and Moser, “Quantum Chemistry” the current literature. T o this exteiit the authors have (Interscience Publishers Inc., X e w Tork, S . T.,1959) prosucceeded in producing the best introduction now available. vides a better introduction t o the current literature in, and The apparatus is described in detail with emphasis 011 the current understanding of, this branch of thecrretical home-made equipment. There is ;i comprehensive treatchemistry. ment of retention parameters and their value to the analyst. LIEPARTMEST OF CHEMISTRY ASD CHEMICAL EXGIKEERINGThe theoretical plate concept is treated adequatell-, but very little uti the rate theory of v m Deemter and others is given. ASD CESTERFOR ADVASCED STUDY ROBERTG . PARR Qualitative and quantitatiw analysis are clearly described. L-SIVERSITY OF ILLISOIS Surnerous key reference. to the literature are given, some URBANA, ILLINOIS ;is late its 1961. Fur the most part, however, thc book represents the statc of the a r t as it esisted in 1959, anti much of the material is froiii the 1956 London Symposium. A . S C H E R ADei)artiiicnt ~~A, Protein Structure. By HAROLD This reviewer would have suggested more emphasis oil of Chemistry, Cornell Uuiversity, Ithaca, S e w York. recent developments at the expense of detailed iristructious Academic Press Inc., 111 Fifth Avenue, S e w York 3, on hotv to build and understand a thermal conductivity S . 17. xiv 305 pp. 16 X 23.5 cm. Price, $8.00. detector (20 p p . ) . For example, the rate theor?; approach is discussed in only six pages; only the abbreviated version This book is based on a series of lectures given by Professor of the van Deemter equation is given, and no discussion of Scheraga in Melbourne, .kustralia, in December, 1959. The recent modifications leading t o optimizing speed. Capillary author has extended the notes of his original lectures in such columns are discussed in two pages and programmed heating a wal- as t o make the treatment of most of the subjects t h a t are included quite complete and informative. D r . Scheraga in one page, which is far less thau these two important topics occupied in two similar books appearing in 1959. 111 other states in his preface that he planned the presentation so t h a t

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