Fj. Devlin et al., AB-INITIO PREDICTION OF VIBRATIONAL ABSORPTION AND CIRCULAR-DICHROISMSPECTRA OF CHIRAL NATURAL-PRODUCTS USING DENSITY-FUNCTIONAL THEORY - ALPHA-PINENE, The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory, 101(51), 1997, pp. 9912-9924
Ab initio density functional theory (DFT) is used to analyze the vibra
tional unpolarized absorption and circular dichroism spectra of the ch
iral monoterpene, alpha-pinene. Large (TZ2P) basis set calculations us
ing the hybrid functionals B3PW91 and B3LYP are in excellent overall a
greement with experiment and permit the assignment of a large fraction
of the fundamental frequencies, The quantitative accuracy of DFT in p
redicting the frequencies, dipole strengths, and rotational strengths
of the fundamentals of alpha-pinene is documented for the B3PW91 and B
3LYP functionals at both TZ2P and 6-31G basis set levels. Hartree-Foc
k/self-consistent field (HF/SCF) calculations have also been carried o
ut in parallel. The accuracy of the HF/SCF methodology is markedly inf
erior to that of DFT. In particular, HF/SCF predictions of the vibrati
onal circular dichroism (VCD) spectrum of alpha-pinene are in very poo
r agreement with experiment.