MICROWAVE DOUBLE RESONANCE EXPERIMENTS ON HCN

Abstract

Modulated microwave double $resonance^{1}$ has been used to study collision-induced transitions between rotational energy levels of HCN for HCN-rare gas collisions (He, Ar, and Xe). It is observed that Ar and Xe have similar effects, while those of He are markedly different. Also, pressure-broadening linewidth parameters for HCN microwave lines have been determined experimentally in HCN-rare gas mixtures. These parameters are used in a modified version of a computer program developed $previously^{2}$ to calculate relative intensities and phase shifts for an assumed set of transition rates.