Effective potentials for H2O-He and H2O-Ar systems. Isotropic induction-dispersion potentials

The vibrational and rotational dependence of the effective isotropic interaction potential of H₂О-Не and H₂О -Аг systems, taken in the form of Lennard-Jones 6-12 potential has been analyzed. The analysis is based on the experimental line broadening (γ) and line shift (δ) coefficients obtained for different vibrational bands of H₂О molecule perturbed by He and Ar. The first and second derivatives of the function С⁽¹⁾(q) for the long-range part of the induction-dispersion potential with respect to the dimensionless normal coordinates q were calculated using literature information for the dipole moment and mean polarizability functions μ(q) and α(q), respectively. These derivatives have been used in the calculations of the quantities which determine the vibrational and rotational dependence of the long-range part of the effective isotropic potential. The optimal set of the derivatives for the function C⁽¹⁾(q) is proposed. The comparison with the experimental data has been performed