Vibronic Coupling in Excited Electronic States Investigated with Resonant 2D Raman Spectroscopy T. Buckup, J.P. Kraack, M.S. Marek and M. Motzkus EPJ Web of Conferences, 41 (2013) 05018 Published online: 13 March 2013 DOI: 10.1051/epjconf/20134105018