✦ LIBER ✦

The origins of avoided crossings in polymer dispersion curves

✍ Scribed by Christopher E. Wozny; Donald W. Noid; Bobby G. Sumpter

Publisher: John Wiley and Sons
Year: 1995
Tongue: English
Weight: 842 KB
Volume: 4
Category: Article
ISSN: 1022-1344
DOI: 10.1002/mats.1995.040040408

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

A purely mathematical heuristic model is examined in order to explain the existence of an avoided crossing between two dispersion curves calculated for a certain potential energy surface designed to simulate the dynamics of a linear polyethylene chain. The model shows that a third mode coupled to a two‐mode Fermi‐resonant system is able to create a marked instability in a vibrational spectrum. It is noted that such an explanation would require a fourth‐order coupling term, which is the reason given for the failure of normal mode analysis to properly identify this dynamical effect.

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