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This paper presents, in a qualitative and practical manner, several aspects of apodization and the utilization of phase information in Fourier transform spectroscopy. For completeness, examples are presented which illustrate the effects on spectra of applying the more common apodizations. The calculation of phase information is formulated, and the type of information available in phase spectra is discussed and illustrated. The use of phase information in phase correction is discussed, and several examples are presented which illustrate the necessity of employing phase correction in conjunction with certain apodizations. Several unique apodizing functions are illustrated, including a sawtooth function which is quite useful for resolution enhancement. Finally, examples of instrumental and self-apodization are presented.

Development of simultaneous multielement atomic absorption analysis has been hampered by a lack of effective multichannel spectrochemical measurement systems. In this study a computer-coupled photodiode array spectrometer is applied to atomic absorption measurements. Using a multielement hollow cathode lamp source and this spectrometer system, a complete “atomic absorption spectrum” can be measured over a range of 130 Å. Both quantitative and qualitative absorption information can be simultaneously acquired for lines of several elements and several lines of one element. Results are presented for multiline atomic absorption of Cr and multielement atomic absorption of Ni and Cr, and Cr and Fe.

state. As shown in curve I of Figure 2, the use of the nitrous oxide flame has no effect on the results. A second way would be burner height studies (the height of the sample beam above the burner head). If non-absorbing

Microwave spectra are reported for species of CH,OPF,, 13CH,0PF,, CH,"OPF,, and CD,OPF, in which the methyl group is cis to the fluorine atoms. The rotational transitions are split by internal rotation of the methyl group. Heights of the potential barrier to internal rotation determined from the splittings are V 3 = 422 i 5 cal/mol for CH,OPF, and 404 i 5 cal/ mol for CD,OPF,. The structural parameters derived from the moments of inertia of the four species are r(PF) = 1.591 * 0.006 A, r(P0) = 1.560 i 0.015 A, r(C0) = 1.446 i 0.005 A, r(CH) = 1.090 i 0.010 A, LFPF = 94.8 f 0.6", LOPF = 102.2 i 1.O0,LCOP=123.7 i 0.5",andLHCH=110.5 ?r 1.0".