Analysis of orientation autocorrelation and cross-correlation functions for polyethylene in the inclusion complex with perhydrotriphenylene

Abstract

The first and second orientation autocorrelation functions have been computed and analysed for polyethylene in the inclusion complex with perhydrotriphenylene at 223, 300, and 373 K. Two coordinate systems have been used-an internal coordinate system defined by the polyethylene chain and an external coordinate system defined by the channel. The orientation autocorrelation functions are denoted by M 1,int (t), M 2,int (t), M 1,ext (t), and M 2,ext (t). Cross-correlation functions have also been computed. The trajectories that provide the raw data are those reported by Zhan and Mattice for n-tetracontane in a channel formed by 90 molecules of perhydrotriphenylene. The results show the dynamics of the internal and external motions occur on different time scales which can be conveniently separated