Molecular dynamics simulations are useful tools to unveil molecular mechanisms of polymer phase separation,self-assembly,adsorption,and so on.Due to large molecular size and slow relaxation of the polymer chains,a gre...Molecular dynamics simulations are useful tools to unveil molecular mechanisms of polymer phase separation,self-assembly,adsorption,and so on.Due to large molecular size and slow relaxation of the polymer chains,a great amount of issues related to large-distance chain displacement cannot be tackled easily with conventional molecular dynamic simulations.Systematic coarse-graining and enhanced sampling methods are two types of improvements that can boost spatiotemporal scales in polymer simulations.We present two typical ways to obtain the coarse-graining potential either by fitting to correct liquid structures or by fitting to available thermodynamic properties of polymer systems.The newly proposed anisotropic coarse-grained particle model can be used to describe aggregation and assembly of polymeric building blocks from disk-like micelles to Janus particles.We also present a stochastic polymerization model combined with coarse-grained simulations to investigate the problems strongly influenced by the coupling of polymerization and excluded volume effects.Finally,a facile implementation of integrated tempering sampling method is illustrated to be very efficient on bypassing local energy minima and having access to true equilibrium polymer structures.展开更多
基金supported by the National Basic Research Program of China(2012CB821500)the National Natural Science Foundation of China(21025416,50930001)
文摘Molecular dynamics simulations are useful tools to unveil molecular mechanisms of polymer phase separation,self-assembly,adsorption,and so on.Due to large molecular size and slow relaxation of the polymer chains,a great amount of issues related to large-distance chain displacement cannot be tackled easily with conventional molecular dynamic simulations.Systematic coarse-graining and enhanced sampling methods are two types of improvements that can boost spatiotemporal scales in polymer simulations.We present two typical ways to obtain the coarse-graining potential either by fitting to correct liquid structures or by fitting to available thermodynamic properties of polymer systems.The newly proposed anisotropic coarse-grained particle model can be used to describe aggregation and assembly of polymeric building blocks from disk-like micelles to Janus particles.We also present a stochastic polymerization model combined with coarse-grained simulations to investigate the problems strongly influenced by the coupling of polymerization and excluded volume effects.Finally,a facile implementation of integrated tempering sampling method is illustrated to be very efficient on bypassing local energy minima and having access to true equilibrium polymer structures.
