Local Structure and Dynamics of Trans-polyisoprene oligomers
Local Structure and Dynamics of Trans-polyisoprene oligomers
复制标题
反式聚异戊二烯低聚物的局部结构和动力学
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
D. Theodorou
中科院分区：
文献类型：
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作者：
R. Faller;F. Mueller;M. Doxastakis;D. Theodorou
以全原子细节模拟反式-1，4-聚异戊二烯低聚物（平均长度为10个单体）的单分散和多分散熔体。力场的发展是通过从头算量子化学和自动生成的经验参数的混合物。NMR和散射实验的比较验证了该模型。局部重定向动力学表明，对于C-H矢量，存在由初始衰减和源自整体重定向的后期去相关组成的两阶段过程。原子模型可以成功地映射到一个简单的模型，只包括珠的单体键弹簧和键角电位。端桥蒙特卡罗作为一个平衡阶段和分子动力学作为后续的模拟方法一起被证明是一个有用的方法，聚合物模拟。
Mono- and polydisperse melts of oligomers (average length 10 monomers) of trans-1,4-polyisoprene are simulated in full atomistic detail. The force field is developed by means of a mixture of ab initio quantum chemistry and an automatic generation of empirical parameters. Comparisons to NMR and scattering experiments validate the model. The local reorientation dynamics shows that for C−H vectors there is a two-stage process consisting of an initial decay and a late-stage decorrelation originating from overall reorientation. The atomistic model can be successfully mapped onto a simple model including only beads for the monomers with bond springs and bond angle potentials. End-bridging Monte Carlo as an equilibration stage and molecular dynamics as the subsequent simulation method together prove to be a useful method for polymer simulations.