Path integral molecular dynamics method based on a pair density matrix approximation: An algorithm for distinguishable and identical particle systems
Path integral molecular dynamics method based on a pair density matrix approximation: An algorithm for distinguishable and identical particle systems
复制标题
DOI：
10.1063/1.1397328
复制
发表时间：
2001-09
影响因子：
4.4
通讯作者：
S. Miura;S. Okazaki
中科院分区：
文献类型：
--
作者：
S. Miura;S. Okazaki
本文对路径积分分子动力学（PIMD）方法进行了扩展，采用了路径作用的有效近似，即对密度矩阵近似。在标准原语近似的基础上，通过引入虚拟动量对同构经典系统的构型进行动态采样。粒子的不可区分性是由粒子排列的伪势来处理的，这是我们之前的扩展[J]。化学。[j].物理学报，2000,16(2)。作为对玻尔兹曼统计方法的测试，我们对液态氦-4在4k下进行了计算。我们发现，采用对密度矩阵近似的PIMD大大减少了计算成本，以获得与原始近似相同的精度水平的结构和动力学性质（使用质心分子动力学近似）。对于相同的粒子，我们进行了计算…
In this paper, the path integral molecular dynamics (PIMD) method has been extended to employ an efficient approximation of the path action referred to as the pair density matrix approximation. Configurations of the isomorphic classical systems were dynamically sampled by introducing fictitious momenta as in the PIMD based on the standard primitive approximation. The indistinguishability of the particles was handled by a pseudopotential of particle permutation that is an extension of our previous one [J. Chem. Phys. 112, 10 116 (2000)]. As a test of our methodology for Boltzmann statistics, calculations have been performed for liquid helium-4 at 4 K. We found that the PIMD with the pair density matrix approximation dramatically reduced the computational cost to obtain the structural as well as dynamical (using the centroid molecular dynamics approximation) properties at the same level of accuracy as that with the primitive approximation. With respect to the identical particles, we performed the calculatio...