A low-scaling method for second order Møller–Plesset calculations
A low-scaling method for second order Møller–Plesset calculations
复制标题
二阶 Møller-Plesset 计算的低尺度方法
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
P. Pulay
中科院分区：
文献类型：
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作者：
S. Saebo;P. Pulay
描述了二阶 Moller-Plesset 微扰理论 (MP2) 的新低阶标度算法。该方法采用局域轨道。然而，与文献中报道的其他局部 MP2 方案相比，保留了对给定轨道对的相关能量有重大贡献的所有原子轨道。如果考虑所有重要的对，我们的方法不会引入显着的近似。然而，该方法旨在描述空间上接近（“强”）对之间的相关性；对于距离较远的配对，可以使用更经济的替代方法。详细描述了该算法，包括同时二指数积分变换方案的新实现。测试计算证明了大型系统的渐近线性缩放。报告了在一台 PC 上执行的强对 MP2 计算，其中包含超过 1800 个契约基函数。由于其较低的缩放比例，MP2 能量的计算比大型系统的 Hartree-Fock 能量的计算更便宜。这已被证明具有很强的货币对相关性，但预计也适用于完整的 MP2 计算。
A new low-order scaling algorithm for second-order Moller–Plesset perturbation theory (MP2) is described. The method employs localized orbitals. However, in contrast to other local MP2 schemes reported in the literature, all atomic orbitals with significant contribution to the correlation energy for a given pair or orbitals are retained. Our approach introduces no significant approximation if all significant pairs are taken into account. However, the method is intended for the description of correlation between spatially close (“strong”) pairs; for distant pairs, more economical alternative methods can be used. The algorithm, including a new implementation of the simultaneous two-index integral transformation scheme, is described in detail. Test calculations demonstrate asymptotic linear scaling for large systems. Strong-pair MP2 calculations with more that 1800 contracted basis functions performed on a single PC are reported. As a consequence of its lower scaling, the calculation of the MP2 energy is less expensive than the calculations of the Hartree–Fock energy for large systems. This has been demonstrated for strong pair correlation but is expected to hold also for full MP2 calculations.