title: Theoretical reproduction of the Q-band absorption spectrum of free-base chlorin.
abstract: The computational results of the features observed in the room-temperature Q-band absorption spectrum of free-base chlorin (H2Ch) are presented. The vibrational structures of the first and second excited singlet states were calculated based on a harmonic approximation using density functional theory and its time dependent extension within the Franck-Condon and Herzberg-Teller approaches. The outcome allowed to identify the experimental bands and to assign them to the specific vibrational transitions. A very good agreement between the simulated and measured wavelengths and their relative intensities provided the opportunity to predict the origin of the S0 → S2 transition which could not be determined experimentally.
authors.affiliation: A. Chełkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland.
authors.forename: Justyna
authors.initials: J
authors.lastname: Wójcik
authors.affiliation: A. Chełkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland.
authors.forename: Alicja
authors.initials: A
authors.lastname: Ratuszna
authors.affiliation: A. Chełkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland.
authors.forename: Jerzy
authors.initials: J
authors.lastname: Peszke
authors.affiliation: A. Chełkowski Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland.
authors.forename: Roman
authors.initials: R
authors.lastname: Wrzalik