REPORT FOR ANALYTICAL CHEMISTS
REFERENCE SUBSTANCES FOR USE IN
ORGANIC MICRO-ANALYSIS
@
ORGANIC ANALYTICAL STANDARDS
Name of substance
Figure 8.
Visible Light Ellipsometer
azimuth angle of this ellipse can be determined by an ellipsometer, shown in Figure 8. In practice, elliptically polarized light is used in the incident beam and adjusted until plane polarized light results in the reflected beam. The angle be tween the polarizer and the quarter wave plate is related to Δ, the phase difference between the light in the two axes of the ellipse. The angle between the polarizer and the ana lyzer is related to the azimuth angle, ψ of the ellipse. These two parameters (taken in conjunction with the refractive index of the film,
the angle of incidence, and the wavelength of the incident light) are combined in a very complex re lationship with thickness which can, however, be dealt with by com puter techniques. Figure 9 shows two curves, each for a different re fractive index, which relate Δ and ψ for transparent films on gallium arsenide. These curves are gener ated by a computer from theory. The determined values of Δ and ψ give a point which, if the refractive index is correct, will fall on the curve and give the thickness. If the point is off the curve, the values
Acetanilide ' O . A . 5 . ' DL-a-Alanine O . A . S . " Anthracene 'O.A.S.' o-Arsanilic acid Coamino - phenyl arsonicacid) Ό.Α.5.' Atropine' O . A S.' Benzoic acid O . A . S . ' 5-Benzyl-thiouronium chloride 'O.A.S.' p-Bromo-benzoic acid O.A.S.' 1-Chloro-2:4-dinitrobenzene 'O.A.S.' Cinnamicacid 'O.A.S. Cyclohexanone2:4-dinitro-phenylhydrazone O . A . S . ' Dibenzyl disulphide 'O.A.S.' m-Dinitro-benzene 'O.A.S.' p-Fluoro-benzoic acid O.A.S.' α-D-Glucose pentaacetate 'O.A.S.' Hexachloro-benzene 'O.A.S.' Hippuric acid O.A.S." 8-Hydroxy-quinoline 'O.A.S.' o-lodo-benzoic acid O.A.S.' Mannitol 'O.A.S.' Melamine O.A.S." p-Nitro-aniline O.A.S.' Phenacetin O.A.S." Phenyl-mercury acetate O.A.S.' Sucrose O . A . S . '
For determination of Nitrogen and N-acetyl Nitrogen and amino-N Carbon and hydrogen Arsenic
N-Methyl Carbon, hydrogen, oxygen and molecu lar weight Nitrogen sulphur and chlorine Carbon, hydrogen and bromine Carbon, hydrogen and chlorine Double bond Carbon hydrogen and nitrogen Sulphur Nitrogen Fluorine O-Acetyl High chlorine Benzoyl Heterocyclic nitrogen Iodine Hydroxyl High nitrogen content, easily broken down Nitrogen, Amino-N and nitro-N Amino-N,N-acetyl and ethoxyl Mercury
Carbon, hydrogen and oxysen Sulphamicacid Nitrogen and sulphur 'O.A.S.' Sulphonai 'O.A.S Sulphur m-Trifluoro-methyl Fluorine benzoic acid 'O.A.S.' Triphenyl-phosphine Phosphorus 'O.A.S.' Vanilin 'O.A.S.' Methoxyl For specifications and prices see the BDH catalogue Available upon request on your organization letter-head
GALLARD-SCHLESINGER CHEMICAL MFG. CORP. Carle Place, Ν. Υ. Π 514 Phone: (516) 333-5600 EXCLUSIVE
Figure 9. Typical Ellipsometer Curves Relating Thickness to Polarization Parameters
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