Toward Ab Initio Anharmonic Vibrational Circular Dichroism Spectra in the Condensed Phase

J Phys Chem Lett. 2012 Jul 5;3(13):1766-73. doi: 10.1021/jz3006139. Epub 2012 Jun 21.

Abstract

The first implementation and calculation of anharmonic VCD rotational strengths for solvated systems is reported. Our approach, rooted in the polarizable continuum model (PCM) and in the second-order vibrational perturbation theory (VPT2), permits not only correction for anharmonicity in the signals associated with fundamental transitions but also calculation of rotational strengths of overtones and combination bands. This allows for a more physically consistent comparison between experiment and calculations together with the analysis of spectral regions dominated by anharmonic effects. The developed model is applied to a few test cases, and the computational outcomes are directly compared with experimental data.

Keywords: chiroptical spectroscopy; polarizable continuum model; solvent effects; vibrational optical activity.