Spectroscopic observation of gold-dicarbide: Photodetachment and velocity map imaging of the AuC_2 anion

摘要

Photoelectron spectra following photodetachment of the gold dicarbide anion, AuC _2 ~-, have been recorded using the velocity map imaging technique at several excitation wavelengths. The binding energy spectra show well-defined vibrational structure which, with the aid of computational calculations and Franck-Condon simulations, was assigned to a progression in the Au-C stretching mode, ν_3. The experimental data indicate that the features in the spectrum correspond to a ~2A′ ← ~3A′ transition, involving states which we calculate to have bond angles ～147° but with a low barrier to linearity.