Study of the H2O dipole moment and polarisability vibrational dependence by the analysis of rovibrational line shifts

The study of the H2O dipole moment mu and polarisability alpha vibrational dependence is based on the comparison of experimental and calculated line shifts induced by argon, nitrogen, and air pressure in different H2O vibrational bands. Obtained dependence alpha on the stretching vibrations is in good agreement with the existing ab initio calculations in the literature, but the dependence alpha on the bending vibration is quite different. To clarify the dependence of mu and alpha on the bending vibration, the shifts of selected H2O lines of the 4 nu(2), 5 nu(2), and 6 nu(2) bands induced by argon, hydrogen and helium pressure are measured with the help of a Bruker IFS HR 125 spectrometer at room temperature with a spectral resolution of 0.01 cm(-1). The comparison of experimental and calculated results with different values of mu and alpha line shifts is given. (C) 2018 Elsevier B.V. All rights reserved.