Electronic photon echo spectroscopy and vibrations
Coupling between electronic and nuclear degrees of freedom in Rhodamine 800 has been studied using fluorescence line narrowing (FLN) and three-pulse photon echo peak shift (3PEPS). From the FLN measurement we extract the Huang-Rhys S-factors and frequencies of 16 Franck-Condon active vibrations clustered in two groups centred around 350 cm(-1) and 1400 cm(-1). The five modes below 500 cm(-1) cover