Premium
Structures of stiff macromolecules of finite chain length near the coil‐globule transition: A Monte Carlo simulation
Author(s) -
Ivanov V. A.,
Stukan M. R.,
Vasilevskaya V. V.,
Paul W.,
Binder K.
Publication year - 2000
Publication title -
macromolecular theory and simulations
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.37
H-Index - 56
eISSN - 1521-3919
pISSN - 1022-1344
DOI - 10.1002/1521-3919(20001101)9:8<488::aid-mats488>3.0.co;2-f
Subject(s) - monte carlo method , chain (unit) , metastability , macromolecule , stiffness , materials science , inverse , statistical physics , molecular physics , thermodynamics , chemistry , chemical physics , physics , geometry , mathematics , biochemistry , statistics , organic chemistry , astronomy
Using a coarse‐grained model of a semiflexible macromolecule, the equilibrium shapes of the chain have been studied varying both the temperature and the chain stiffness. We have applied Monte Carlo techniques using the bond fluctuation model for a chain length of N = 80 effective monomers, and two different types of interactions: a potential depending on the angle between successive bonds along the chain to control the chain stiffness, and an attractive interaction between non‐bonded effective monomers to model variable solvent quality. In a diagram of states where chain stiffness and inverse temperature are used as variables, we find regions where the chain exists as coil, as spherical globule, and as toroidal globule, respectively. Some of these regions are not limited by sharply defined boundaries, but rather wide two‐state coexistence regions occur in between them, where also intermediate metastable structures (such as rods and disks) occur. Recording histograms of energy, orientational order parameters, etc., which exhibit a two‐peak structure in the two‐state coexistence regions, we perform a subensemble analysis of the individual structures corresponding to these peaks.