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Updated: Mar 15, 2026

Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
Published on: April 28, 2016
Can the Resonance Raman Optical Activity Spectrum Display Sign Alternation?
Luciano N Vidal1, Tommaso Giovannini2, Chiara Cappelli2
1Universidade Tecnológica Federal do Paraná , Rua Deputado Heitor de Alencar Furtado, 4900, 81280-340, Curitiba, Brazil.
Abstract:
The monosignate character of resonance Raman optical activity (RROA) spectra has been often taken as granted in experimental and computational approaches, on the basis of basic theoretical approximations only considering resonance with a single electronic state of the molecule and the scattering process to be governed by the Franck-Condon mechanism. We show in this letter for the first time that, by resorting to a fully quantum mechanical (QM) methodology able to take into account all terms entering the general definition of RROA, and which considers excited state interference and Herzberg-Teller effects, sign alternation and at the same time intensity enhancement in RROA spectra is obtained. Such features constitute an important milestone toward the exploration of RROA of a wide range of chiral biological molecules.
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