Vibrational-circular-dichroism spectra of alpha-pinene beta-pinene and nopinone

摘要

The vibrational circular dichroism (VCD) spectra of the title compounds were recorded in the range of 800 - 1500 cm$+$MIN@1$/ using a Nicolet 8000 FT-IR interferometer. They were assigned based on observed absorption spectra, calculated frequencies using scaled ab initio 3 - 21 G force fields, and 3 - 21 G atomic polar tensor (APT) intensities. To interpret the observed VCD features fixed partial charge (FPC), charge flow (CF) and APT intensities were used. APT reproduces the VCD intensities reasonably well. Complete matrices of STO-3G Mulliken charge flow parameters (CFPs) augmenting FPC-VCD intensities revealed charge flow governed modes and certain inadequacies of the CF model.