Helium broadening parameters of water vapor in the 10,200–11,200 cm⁻¹ spectral region

The He-broadening (γ) and shift (δ) coefficients of 76 rovibrational transitions belonging to the 3ν₁, 3ν₃, ν₁ + 2ν₂ + ν₃, and 2ν₁ + ν₃ vibrational bands of H₂O molecule were measured in the spectral range between 10,200 and 11,200 cm⁻¹ with the spectral resolution of 0.01 cm⁻¹ using a Bruker IFS 125HR FTIR spectrometer. The calculations of γ and δ were performed in the framework of the semi-classical method. It was shown that the vibrational dependence of the long-range as well as the short-range parts of an isotropic H₂O-He interaction potential influence substantially the calculated broadening coefficients γ. The vibrationally and rotationally dependent analytical model for the broadening coefficients calculation is presented and discussed.