Dubecký, M. Derian, R. Horváthová, L. Allan, Michael Štich, I. 2011-10-17 Singlet and triplet excited states of trans-azobenzene have been measured in the gas phase by electron energy loss spectroscopy (EELS). In order to interpret the strongly overlapping singlet and triplet bands in the spectra a set of large-scale correlated quantum Monte-Carlo (QMC) simulations was performed. The EELS/QMC combination of methods yields an excellent agreement between theory and experiment and for the two low-lying excited singlet and two low-lying triplet states permitted their unambiguous assignment. In addition, EELS revealed two overlapping electronic states in the band commonly assigned as S2, the lower one with a pronounced vibrational structure, the upper one structureless. Finally, the agreement between theory and experiment was shown to further increase by taking computationally into account the finite temperature effects. application/pdf https://folia.unifr.ch/global/documents/302363 https://folia.unifr.ch/documents/302363/files/all_dts.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1039/C1CP22520K info:eu-repo/semantics/openAccess License undefined Physical Chemistry Chemical Physics. - 2011, vol. 13, p. 20939-20945 info:eu-repo/classification/udc/54 Disentanglement of triplet and singlet states of azobenzene: direct EELS detection and QMC modeling http://purl.org/coar/resource_type/c_6501