电场环境下纳米通道内水分子传输行为的MD模拟研究

MD Simulations of the Water Transportation in Nanochannels under the Environments of Electric Fields

纳米通道内的水分子传输是近年来分子动力学(MD)模拟研究的热点之一。本文综述了电场对纳米通道中水分子传输行为影响的研究成果,主要介绍了三种施加电场的方法:在通道附近加电荷、在通道两侧的水相中加离子或带电荷的氨基酸以及对纳米通道直接施加电场。并报道了各类电场对纳米通道内水的填充平衡及相变行为、水分子偶极取向、水流量、水扩散速率等产生的影响,以及加电场的各种相关应用,如水流开关、信号传输、水泵及存储器等。最后,剖析了电场环境下MD模拟研究中尚待解决的问题。

The transportation properties of water in nanochannels have been widely studied by molecular dynamics （MD） simulations. In the environments of electric fields, the behaviors of water, such as molecular dipole orientations, flux, diffusion rate, water filling/empty equilibriums and phase-transition processes, etc. , are much influenced. This review surveys the methods of introducing electric fields in MD simulations, including assigning charges near tubes, adding ions or charged amino acids to the water phases on both sides of nanotubes, and directly applying electric fields through the whole nanotubes. Besides, the relevant applications using electric fields, such as flow switch, signal transmission, water pump, stable storage, etc. , are also included. Finally, some issues in the relevant MD studies are presented.