The electronic spectrum of jet-cooled copper hydrosulfide (CuSH)

Abstract

The electronic spectrum of copper hydrosulfide (CuSH) has been observed for the first time. CuSH and CuSD were produced in a pulsed discharge jet by the reaction of sputtered copper atoms with H(2)S or D(2)S. Strong laser-induced fluorescence bands observed in the 515-470 nm region were assigned as the ~A (1)A"-X (1)A' band system based on detailed rotational analysis and the correspondence with the predictions of our CCSD(T)6-311++G(3df,3pd) ab initio calculations. The laser-induced fluorescence and single vibronic level emission spectra consist primarily of a short progression in nu(3), the Cu-S stretching mode, indicative of only modest structural changes on electronic excitation. The rotational constants of four isotopomers of CuSH were used to determine effective zero-point structures in the combining states as r"(CuS)=2.0916(3) A, r"(SH)=1.364(3) A, theta"=93.5(3) degrees , r'(CuS)=2.172(3) A, r'(SH)=1.408(23) A, and theta'=93.5(24) degrees . A comparison of the ground state structures of the known metal hydrosulfides shows that they can be considered to be metal-substituted hydrogen sulfides. The electronic spectra and molecular structures of CuOH and CuSH are compared and contrasted.