Vibronic activity and the change in geometrical structure accompanying the 580 nm electronic transition of CrO2Cl2

Publisher Website
Google Scholar
Abstract
An analysis is presented for the vibronic intensity distribution in absorption and emission spectra of the 580 nm band system of CrO2Cl2. The marked variability of the activities of ν 2 and ν 3 in the various spectra is shown to arise from a strong rotation of the form of the normal coordinates on excitation (Duschinsky effect). It is confirmed that the 217 cm-1 interval between the d and a absorption bands corresponds to an a 1 normal mode which is assigned to ν′3, mainly symmetric CrCl2 stretching. The Franck-Condon analysis is combined with the rotational constants of Blazy and Levy to yield values for the changes in geometrical structure in the excited state. These are discussed in terms of the electronic structure of CrO2Cl2.