Vol. 30, issue 11, article # 5

Abstract:

An atom-atom interaction potential for H₂O–A system is proposed in the form which depends on the normal coordinates q of H₂O molecule. The vibrational and rotational contributions in this potential are calculated for H₂O–He and H₂O–Ar systems. It is shown that the excitation of the stretching modes of the vibrations in H₂O molecule leads to an increase in the calculated broadening coefficients γ. In the case of broadening by He, γ increases by 15% for the lines with the rotational quantum number K_a = 9 of the lower state in the transition. In the case of broadening by Ar, this increase is 4%.

Keywords:

atom-atom potential, H2O–He, H2O–Ar, collisional broadening

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