Theoretical Vibrational Spectra Compared to the Experiment and the Anomeric Effect in 2-chloro-1,3,2-dioxaphosphorinane-2-oxide, -sulfide, and -selenide. II. Vibrational Spectra and Assignments
H.M. Badawi, W. F??rner
Department of Chemistry King Fahd University of Petroleum and Minerals
forner@kfupm.edu.sa
Ключевые слова: vibrational spectra, 2-chloro-1,3,2-dioxaphosphorinane-2-oxide, -sulfide, -selenide, DFT/B3LYP, 6-311G** basis set
Страницы: 277-283
Аннотация
2-Chloro-1,3,2-dioxaphosphorinane-2-oxide, -sulfide, and -selenide are studied with the help of DFT/B3LYP and several ab initio methods using a 6-311G** basis set. However, due to rather large relative energies of higher conformers in all three cases, the conformational equili-brium mixture contains more than 95 % (see the preceding paper in this Journal) of the lowest chair-equatorial conformer (this indicates that the P=X bond is in the equatorial position), so we do not find any conformer bands in the experimental spectra and calculate our theoretical ones for the assignment only fr om the chair-equatorial conformer. The vibrational infrared and Raman spectra were calculated and are in fair agreement with their experimental counterparts. Potential energy distribution calculations are performed, and the theoretical modes wh ere an experimental counterpart could be found to symmetry coordinates are assigned.
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