Vibronic dephasing of anharmonic molecules. II. Impurity molecules isolated in low-temperature matrices

Abstract

The quantum‐mechanical theory of vibronic dephasing presented in the first paper of this series is applied to the case of a diatomic impurity dissolved in a solid rare‐gas host. An explicit expression for the pure dephasing rate T_2′^(−1) is derived in terms of microscopic properties of the impurity and host, and the effects of variations in the parameters characterizing these properties are investigated. The expression for T_2′^(−1) is applied specifically to the system Cl_2/Ar in order to relate the results to those of previous classical‐trajectory calculations and of experimental measurements. The significance of anharmonicity in the intramolecular potential curve (of the impurity) is demonstrated.