title: Vibrationally resolved photoelectron imaging of Cu2H- and AgCuH- and theoretical calculations.
abstract: Vibrationally resolved photoelectron spectra have been obtained for Cu(2)H(-) and AgCuH(-) using photoelectron imaging at 355 nm. Two transition bands X and A are observed for each spectrum. The X bands in both spectra show the vibration progressions of the Cu-H stretching mode and the broad peaks of these progressions indicate significant structural changes from Cu(2)H(-) and AgCuH(-) to their neutral ground states. The A bands in the spectra of Cu(2)H(-) and CuAgH(-) show stretching progressions of Cu-Cu and Ag-Cu, respectively. The contours of these two progressions are pretty narrow, indicating relatively small structural changes from Cu(2)H(-) and AgCuH(-) to their neutral excited states. Calculations based on density functional theory indicate that the ground states of Cu(2)H(-) and AgCuH(-) and the first excited states of their neutrals are linear, whereas their neutral ground states are bent. The photoelectron detachment energies and vibrational frequencies from these calculations are in good agreement with the experimental observations. Especially, the theoretical predication of linear structures for the anions and the neutral excited states are supported by the spectral features of A bands, in which the bending modes are inactive. Comparisons among the vertical detachment energies of Cu(2)H(-), AgCuH(-), and their analogs help to elucidate electronic characteristics of coinage metal elements and hydrogen in small clusters.
authors: State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors: Hua
authors: H
authors: Xie
authors: Xiaoyi
authors: X
authors: Li
authors: Lijuan
authors: L
authors: Zhao
authors: Zhiling
authors: Z
authors: Liu
authors: Zhengbo
authors: Z
authors: Qin
authors: Xia
authors: X
authors: Wu
authors: Zichao
authors: Z
authors: Tang
authors: Xiaopeng
authors: X
authors: Xing