Rotational self-correlation functions of N₂O dissolved in liquid SF₆

Abstract

In a recent paper (1986, Molec. Phys., 59, 985), it was shown that rotational correlation functions of N₂O dissolved in SF₆ may be reproduced using a simulated two Lennard-Jones centre liquid model. Our simulations provided an explanation of why simple theoretical models fail to describe the rotational motion. Following the same method, we investigate, in this paper, the models based on the memory function formulation. The main conclusions are that one of the models is particularly well adapted for the low reduced torque cases (≃16) while another is good for the high reduced torque cases (≃74). The simulated reduced torque range (20–50) corresponding to our experimental data lies precisely between these limits. This explains why the system N₂O/SF₆ was not correctly approximated by usual memory function models.