LIPS method : an improved IPS method using linear combinations of basis potentials
LIPS method : an improved IPS method using linear combinations of basis potentials
复制标题
LIPS 方法：使用基电位线性组合的改进 IPS 方法
DOI：
10.1021/ct3003805
复制
发表时间：
2012
影响因子：
5.5
通讯作者：
Kenji
中科院分区：
文献类型：
--
作者：
Takahashi;Kazuaki;Tetsu;Narumi;Suh;Donguk;Yasuoka;Kenji
各向同性周期和（IPS）是一种计算长程相互作用的技术，与传统的晶格和方法不同。IPS方法与格点和方法的区别在于长程相互作用计算中遥像的形状和分布。晶格和计算中使用的图像与周期性边界条件生成的图像相同，并且离散地定位在空间中的晶格点处。用于IPS计算的图像是“假想的”，这意味着它们不明确存在于模拟系统中，并且围绕每个粒子各向同性和周期性地分布。原始IPS方法存在两个不同版本。IPSn方法用于计算点电荷，而IPSp方法用于计算极性分子。然而，IPSn和IPSp在模拟本体水或水-蒸汽界面系统方面都有其优点和缺点。在散装水系统中，IPSn的截止半径效应强烈影响的配置，而IPSp不提供足够的水蒸气界面系统的估计，除非使用很长的截止半径。为了扩展IPS方法的适用范围，提出了一种改进的IPS方法，即基于线性组合的各向同性周期和（LIPS）方法，该方法在均相和非均相体系中都具有更好的精度。这种改进的IPS方法使用了基电位的线性组合。我们进行了分子动力学（MD）模拟散装水和水蒸汽界面系统的LIPS方法的准确性进行评估。对于本体水系统，LIPS方法在估计热力学和构型性质方面具有比IPSn更好的准确性，而无需用于IPSp的反电荷假设。对于水蒸气界面体系，LIPS比IPSp具有更好的准确性，并正确地估计热力学和构型性质。总之，LIPS方法可以成功地估计极性分子系统的均相和非均相系统，具有良好的精度。
Isotropic periodic sum (IPS) is a technique that calculates long-range interactions differently than conventional lattice sum methods. The difference between IPS and lattice sum methods lies in the shape and distribution of remote images for long-range interaction calculations. The images used in lattice sum calculations are identical to those generated from periodic boundary conditions and are discretely positioned at lattice points in space. The images for IPS calculations are “imaginary”, which means they do not explicitly exist in a simulation system and are distributed isotropically and periodically around each particle. Two different versions of the original IPS method exist. The IPSn method is applied to calculations for point charges, whereas the IPSp method calculates polar molecules. However, both IPSn and IPSp have their advantages and disadvantages in simulating bulk water or water–vapor interfacial systems. In bulk water systems, the cutoff radius effect of IPSn strongly affects the configuration, whereas IPSp does not provide adequate estimations of water–vapor interfacial systems unless very long cutoff radii are used. To extend the applicability of the IPS technique, an improved IPS method, which has better accuracy in both homogeneous and heterogeneous systems has been developed and named the linear-combination-based isotropic periodic sum (LIPS) method. This improved IPS method uses linear combinations of basis potentials. We performed molecular dynamics (MD) simulations of bulk water and water–vapor interfacial systems to evaluate the accuracy of the LIPS method. For bulk water systems, the LIPS method has better accuracy than IPSn in estimating thermodynamic and configurational properties without the countercharge assumption, which is used for IPSp. For water–vapor interfacial systems, LIPS has better accuracy than IPSp and properly estimates thermodynamic and configurational properties. In conclusion, the LIPS method can successfully estimate homogeneous and heterogeneous systems of polar molecular systems with good accuracy.