Vibrational Dependences of Broadening and Shift Coefficients of H2O Absorption Lines Perturbed by Ne, Kr, and Xe

Abstract

The dependence of the intermolecular interaction potentials on the vibrational quantum numbers of the H₂O molecule is derived for the H₂O–Ne, H₂O–Kr, and H₂O–Xe systems. The broadening γ and shift δ coefficients are calculated for seven vibrational bands ν₁, ν₂, ν₃, 2ν₂, ν₁ + ν₂, ν₂ + ν₃, and ν₁ + ν₂ + ν₃ of the H₂O molecule from the absorption region 640–9550 cm⁻¹. An analytical formula is suggested for calculation of the broadening coefficients γ at T = 296 K. It is shown that the excitation of stretching modes of the vibrations in the H₂O molecule increases the broadening coefficients. The influence of the bending vibrations on γ is insignificant.