The laser-induced fluorescence spectroscopy of gold monoxide: B2σ--X2π3/2 transition

The electronic spectrum of the gaseous gold monoxide molecule has been investigated in the range of 16000-18500 cm(-1) using laser induced fluorescence spectroscopy and single vibronic level emission spectra. Five rotationally resolved vibronic bands are observed and assigned to the transitions B-2 sigma(-) (v' = 0-4) -X-3/2(2) (v'' = 0), in which the 0-0 transition is observed for the first time. The molecular constants of the excited state B-2 sigma(-) are obtained by a rotational analysis of the spectra. The spin-orbit coupling constant and the vibrational constants of the ground state X-i(2) are determined with the accuracy improved by one order of magnitude. The lifetimes of most observed bands are also measured for the first time.