Investigation of the inter-molecular dynamics of non-dipolar molecules using the rotational velocity correlation function

Abstract

The rotational velocity correlation function is used to assess the Colpa–Ketelaar and Litovitz models of the intermolecular motions of compressed gaseous and liquid non-dipolar molecules which give rise to their broad band absorptions in the far infra-red (2–200 cm^–1). The simple Colpa–Ketelaar bimolecular collision model is found to be satisfactory only in the case of N₂(g). The Litovitz model of the liquid state, although approximate in derivation, is rather more successful, but does not show the very short time (ca. 0.1–0.5 ps) oscillations observed in the experimental functions up to 2.0 ps.