Investigation of the absorptions of monoisotopic OsO4 with CO2 and N2O laser lines with saturation spectroscopy

Abstract

Some absorption features of monoisotopic 186–190,192OsO4 have been studied by saturated absorption using low-pressure CO2 and N2O lasers. Ground-state absorptions of the ν3 fundamental band were distinguished from hot-band absorptions by investigation of the linear absorption coefficients, and were assigned on the basis of frequency calculations. In addition the vibrational transition moment was evaluated. A few lines were found, which, due to their unusual saturation properties, were identified as forbidden transitions arising from off-diagonal terms of a sixth rank tensor in the effective Hamiltonian. Their observation permits a value of the tensor centrifugal distortion constant to be derived: Dt = (2.045 ± 0.018) × 10-9 cm-1.