Electronically excited states in size selected solvated alkali metal atoms. I. First observation in NaNH3 by resonant two color two photon ionization

Resonant two color two photon ionization is used to investigate the first electronically excited state of NaNH3 as a first example of size selected, solvated alkali metal atoms systems (alkali⋅solventn). The observed spectrum shows a complex vibrational and rotational structure. The 0-0 transition is found at 12 220 cm−1 (1.52 eV), in good agreement with recent theoretical calculations. With increasing laser power ionic fragments of the molecule are seen, indicating possible new avenues to study the dynamics of charge transfer processes in this type of model system.