Analysis of Orientation Autocorrelation and Cross-Correlation Functions for Polyethylene in the Inclusion Complex with Perhydrotriphenylene
Macromolecules, cilt.26, sa.12, ss.3137-3142, 1993 (Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 26 Sayı: 12
- Basım Tarihi: 1993
- Doi Numarası: 10.1021/ma00064a023
- Dergi Adı: Macromolecules
- Derginin Tarandığı İndeksler: Scopus
- Sayfa Sayıları: ss.3137-3142
- Boğaziçi Üniversitesi Adresli: Evet
Özet
The first and second orientation autocorrelation functions have been computed and analyzed 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 M1,int(t), M2,int(t), M1,ext(t), and M2,ext(t). Cross-correlation functions have also been computed. The trajectories that provide the raw data are those reported by Zhan and Mattice (Macromolecules 1992, 25, 4078) 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. The rigid-body rotation about the chain axis dominates the overall chain motion. The short-term memory of the direction of this rotation produces a slight overshoot to the decay of M1,ext(t) and M2,ext(t) at 223 and 300 K. This feature can be rationalized by a simple model for the rigid-body rotation. The internal motions are of higher frequency. They are dominated by the librational motions of internal CC bonds, on a picosecond time scale, within the trans rotational isomeric state. © 1993, American Chemical Society. All rights reserved.