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Updated: Dec 26, 2025

Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds
Published on: October 12, 2018
Theoretical study of the Raman optical activity spectra of with M = Co, Rh
Laura Abella1, Herbert D Ludowieg1, Jochen Autschbach1
1Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York.
Abstract:
Vibrational Raman optical activity (ROA) spectra were calculated under off-resonance, near-resonance, and at-resonance conditions for (A) and under off-resonance conditions for (B) using a new driver software for calculating the ROA intensities from complex (damped) time-dependent linear response Kohn-Sham theory. The off-resonance spectra of A and B show many similarities. At an incident laser wavelength of 532 nm, used in commercial ROA spectrometers, the spectrum of A is enhanced by near-resonance with the ligand-field transitions of the complex. The near-resonance spectrum exhibits many qualitative differences compared with the off-resonance case, but it remains bi-signate. Even under full resonance with the ligand-field electronic transitions, the ROA spectrum of A remains bi-signate when the electronic transitions are broadened such as to yield absorption line widths that are comparable with those in the experimental UV-vis absorption and electronic circular dichroism spectra.
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