High-resolution spectroscopic study of 2ν1, 2ν3 and ν1+ν3 stretching states: the local-mode effects of H2Se

High-resolution spectra of the coupled 2ν1, 2ν3 and ν1+ν3 states of H2Se have been studied. The vibration–rotation transitions of H2nSe (n= 82, 80, 78, 77 and 76) were assigned by using the ground-state combination differences and least-squares fitted to yield the vibration–rotation parameters. Several striking local-mode effects are observed and discussed.