Quantum Monte Carlo studies of vibrational states in molecules and clusters
Quantum Monte Carlo studies of vibrational states in molecules and clusters
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分子和团簇振动状态的量子蒙特卡罗研究
DOI：
10.1016/0370-1573(91)90136-a
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
R. Watts
中科院分区：
文献类型：
--
作者：
M. Suhm;R. Watts
近年来，量子蒙特卡罗方法得到了较为详细的研究[1]。应用范围从电子结构的从头计算到量子固体的模拟。在这篇文章中，我们将描述使用量子蒙特卡罗来计算范德华团簇的振动本征函数和相应的性质。我们的重点将放在模拟技术上，全面讨论误差的来源和需要更多研究的领域，而不是我们结果的物理意义。我们的大部分讨论将基于水团簇的性质的计算，主要是因为这个系统受到了最多的关注。文献中介绍了量子蒙特卡罗计算的两种基本方法：Kalos的格林函数方法和Anderson的扩散模拟方法。Ceperley和Alder已经给出了一个介绍性调查[4]。我们的计算完全基于扩散方法，建议读者查阅安德森的论文，以获得对该方法的基本描述。起始点是含时薛定谔方程，对于质量为m，~的N个粒子系统，它是
Quantum Monte Carlo methods have been studied in some detail during recent years [1]. Applications have ranged from ab initio calculations of electronic structure to simulations of quantum solids. In this article we will describe the use of quantum Monte Carlo to calculate the vibrational eigenfunctions, and corresponding properties, of Van der Waals clusters. Our emphasis will be on the simulation techniques, with a comprehensive discussion of sources of error and areas which require more research, rather than on the physical significance of our results. Much of our discussion will be based on calculations of the properties of water clusters, primarily because this system has had the most attention. However, we will also mention some recent results on other hydrogen bonded Van der Waals clusters.Two basic methods for quantum Monte Carlo calculations have been described in the literature, the Green’s function approach of Kalos [2] and the diffusion simulation developed by Anderson [3]. An introductory survey has been given by Ceperley and Alder [4]. Our calculations are based entirely on the diffusion method, and the reader is urged to consult the papers of Anderson for an elementary description of this approach. The starting point is the time-dependent Schrödinger equation which for a system of N particles of mass m,,~ is