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arXiv physics/0409087physics.comp-ph
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用量子蒙特卡罗方法精确、高效和简单地计算力

Accurate, efficient and simple forces with Quantum Monte Carlo methods

Simone Chiesa, David Ceperley, Shiwei Zhang

摘要:

使用量子蒙特卡罗方法计算离子力一直是一个挑战。我们介绍了一个简单的程序,根据已知的物理电子密度的属性,使赫尔曼-费曼估计有限的方差。用Slater-Jastrow试探波函数得到了分子H $_2$,LiH,CH $_4$,NH $_3$,H $_2$ O和HF的精确几何构型.谐波频率也与实验符合得很好。还讨论了一种对偶抽样方法,以进一步减少方差。

英文摘要:

Computation of ionic forces using quantum Monte Carlo methods has long been a challenge. We introduce a simple procedure, based on known properties of physical electronic densities, to make the variance of the Hellmann-Feynman estimator finite. We obtain very accurate geometries for the molecules H$_2$, LiH, CH$_4$, NH$_3$, H$_2$O and HF, with a Slater-Jastrow trial wave function. Harmonic frequencies for diatomics are also in good agreement with experiment. An antithetical sampling method is also discussed for additional reduction of the variance.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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