MONTE CARLO SIMULATION OF POLYMER CHAIN COMFORMATIONS: COMFORMATIONAL ENTROPY OF SINGLE CHAIN
聚合物链构象的Monte Carlo模拟:单链的构象熵

In this paper a new approximate method, which is called "The Conformational Counting Method", for estimating the Conformational entropy of polymer chains has been proposed. The method is applied to random self-avoiding walks on simple cubic lattice. In the range of chain step number n= 7~19 the entropy data obtained by this method are consistent perfectly with their precise value and the deviation is smaller than 0.04% (sample sizes- 2,000). In the range of n up to 26 of chains confined in a cubic box of side length 2 the entropy data are consistent very good also with their precise value obtained by means of directly counting all conformations. The deviation is smaller than 0.6% (sample sizes ~2,000). In the range of n up to 2,100 of free chains, the entropy -data confirm the renormalization group prediction:where k is Boltzmann constant,u = 4.6838, r = 7/6 and C0 = 1.17. For all chain step number deviations are negative and within 0.8%(sample sizes~ 300). The way to improve the accuracy is suggested.