Solvent perturbations of extravalence excitations of atomic Xe by rare gases at high pressures

In this paper we present the results of an experimental study of the lowest doublet excitations (1S0→3P1 and 1S0→1P1) of atomic xenon in dense supercritical fluid neon and helium and the 1S0→1P1 xenon excitation in dense supercritical and subcritical fluid argon. The spectral shift, the linewidth, the first moment, and the second moment of the absorption bands exhibit a strong density and a weak temperature dependence. The semiclassical statistical theory of line shapes was applied for the calculations of the first moment, the second moment, and the entire line shape. By fitting to the experimental moments over a broad density range, the excited state guest–host interaction potential parameters were derived. An analysis of the density dependence of the splitting and of the intensity ratio of the Xe doublet perturbed by high pressure rare gases was provided.