Authors Chervanyov, A. ; Heinrich, G.
Title Flory radius of polymers in a periodic field: An exact analytic theory
Date 24.11.2007
Number 14926
Abstract We found an exact expression for the Flory radius RF of Gaussian polymers placed in an external periodic field. This solution is expressed in terms of the two parameters · and a that describe the reduced strength of an external field and the period of the field to the polymer gyration radius ratio, respectively. RF is found to be a decaying function of · for any values of a . Provided that the gyration radius is of the order of the period of an external field or less, the ground-state (GS) approximation of the exact result for RF is shown to give qualitatively incorrect results. In addition to the "ground-state" contribution, the exact solution for RF contains an additional term that is overlooked by the GS approximation. This term gives rise to the fact that RF as a function of · exhibits power law behavior (rather than exponential decay obtained from the GS result) once · exceeds the threshold value ·con .
Publisher European Physical Journal E
Citation European Physical Journal E 24 (2007) 271-276

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