Intermolecular exciton coupling and vibronic effects in solid-state circular dichroism: a case study.

TitleIntermolecular exciton coupling and vibronic effects in solid-state circular dichroism: a case study.
Publication TypeBook
Year of Publication2013
AuthorsPescitelli, G, Padula, D, Santoro, F
Series TitlePhysical chemistry chemical physics : PCCP
Volume15
Series Volume3
Number of Pages795–802
ISBN1463-9084
Abstract

The electronic circular dichroism (CD) spectrum of the sesquiterpenoid 1$\beta$,10$\beta$-epoxydesacetoxymatricarin (1) measured in the microcrystalline solid state differs from the solution one in the appearance of a pronounced vibrational fine structure in the long-wavelength region (n-$π$* enone transition) and of a new moderately intense band in the $π$-$π$* region. TDDFT CD calculations were run on input structures derived from the X-ray geometry of 1 to reproduce the impact of exciton-type couplings between proximate molecules in the crystals. The vibrational structure of the CD spectrum was also reproduced for the isolated molecule by modelling the potential energy surfaces at the harmonic level and taking into account Duschinsky and Herzberg-Teller effects.

URLhttp://www.ncbi.nlm.nih.gov/pubmed/23203006
DOI10.1039/c2cp43660d