Journal
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
Volume 263, Issue -, Pages 34-40Publisher
ELSEVIER SCIENCE SA
DOI: 10.1016/j.jphotochem.2013.04.014
Keywords
CASSCF; CASPT2; Multi-reference; Excited states; Photoswitches
Categories
Funding
- German Science Foundation DFG via the Collaborative Research Center [SFB677]
Ask authors/readers for more resources
Knowledge about the character of electronic states involved in ultrafast photoreactions is essential for understanding the dynamics leading to static and transient experimental spectra. Here we present a detailed study of the three lowest-energy electronic states of the photochromic switch methylfurylfulgide in its Z-form and of their changes as they approach the S1S0-conical intersection that facilitates the formation of E-methylfurylfulgide. We studied the molecular energy landscape by identifying important points along the reaction coordinate (Franck-Condon point, S-1-energy minimum and S1S0-conical intersection) by state-averaged CASSCF(10,9)/6-31g(d,p) calculations, assigned the character of the three lowest electronic states at these points and verified our classifications by CASPT2(18,13) calculations in a basis of polarised triple-zeta quality for the atoms relevant to the reaction and polarised double-zeta for the others. In contrast to the E -> Z interconversion, it turns out that a proper active space for the Z -> E interconversion should consist not only of pi orbitals but should contain also orbitals of n character. We expect this to experimentally manifest itself in visible differences between Z -> E and E -> Z behaviour. (C) 2013 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available