Difference frequency laser spectroscopy of SH3+: A simultaneous analysis of the ν1 and ν3 fundamental bands

Abstract

The ν1 and ν3 fundamental bands of SH3+ have been observed in absorption by using a difference frequency laser system in a hollow cathode discharge cell. Observed spectra show complications due to vibration-rotation interactions between the v1 = 1 and the v3 = 1 states. The molecular constants are determined by a least-squares analysis. Observations of “forbidden” transitions enhanced by higher-order vibration-rotation interactions allow us to determine the rotational constants about the molecular axis. The major molecular constants determined are (in cm−1) Ground statev1=1 statev3=1 stateν02521.04816(40)2525.74710(32)B4.89464187(83)4.843738(25)4.845719(18)C4.228258(36)4.188702(42)4.207978(31)(Cζ)30.092352(66)q3(0)-0.010910(41)Z13(0)-0.01018(55)