Influence of single particle orbital sets and configuration selection on multideterminant wavefunctions in quantum Monte Carlo.
Influence of single particle orbital sets and configuration selection on multideterminant wavefunctions in quantum Monte Carlo.
复制标题
单粒子轨道集和构型选择对量子蒙特卡罗多行列式波函数的影响。
DOI：
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发表时间：
2015
影响因子：
4.4
通讯作者：
M. Morales
中科院分区：
文献类型：
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作者：
R. Clay;M. Morales
多行列式波函数，虽然在量子化学中有着悠久的历史，但越来越多地用于高精度的量子蒙特卡罗计算。由于QMC的准确性最终受到试探波函数的质量的限制，多斯莱特行列式波函数提供了一个有吸引力的替代斯莱特-杰斯特罗和更复杂的波函数的原因有几个。它们可以有效地计算，直接优化，并通过增加所包含的决定因素的数量来系统地改进。尽管他们的潜力，但是，收敛性能的多斯莱特行列式波函数相对于轨道集的选择和激发行列式的选择知之甚少，这阻碍了这些波函数的应用到大型系统和固体。在本文中，通过执行QMC计算的平衡和拉伸的碳二聚体，我们发现，收敛的恢复相关能量相对于数量的决定因素可以依赖于相当强烈的基组和决定因素的选择方法，特别是在有很强的相关性。我们证明，适当选择的轨道集和行列式选择技术，从量子化学方法可以显着减少所需的数量的决定因素（从而计算成本），以达到给定的准确性，我们认为，明确需要一个自动QMC的方法选择决定因素和生成最佳的轨道集。
Multideterminant wavefunctions, while having a long history in quantum chemistry, are increasingly being used in highly accurate quantum Monte Carlo calculations. Since the accuracy of QMC is ultimately limited by the quality of the trial wavefunction, multi-Slater determinants wavefunctions offer an attractive alternative to Slater-Jastrow and more sophisticated wavefunction ansatz for several reasons. They can be efficiently calculated, straightforwardly optimized, and systematically improved by increasing the number of included determinants. In spite of their potential, however, the convergence properties of multi-Slater determinant wavefunctions with respect to orbital set choice and excited determinant selection are poorly understood, which hinders the application of these wavefunctions to large systems and solids. In this paper, by performing QMC calculations on the equilibrium and stretched carbon dimer, we find that convergence of the recovered correlation energy with respect to number of determinants can depend quite strongly on basis set and determinant selection methods, especially where there is strong correlation. We demonstrate that properly chosen orbital sets and determinant selection techniques from quantum chemistry methods can dramatically reduce the required number of determinants (and thus the computational cost) to reach a given accuracy, which we argue shows clear need for an automatic QMC-only method for selecting determinants and generating optimal orbital sets.
影响因子：
4.4
作者：
Cleland, D. M.;Booth, George H.;Alavi, Ali
通讯作者：
Alavi, Ali
影响因子：
4.4
作者：
Booth, George H.;Cleland, Deidre;Alavi, Ali
通讯作者：
Alavi, Ali