Automatically generated Coulomb fitting basis sets: design and accuracy for systems containing H to Kr.
Automatically generated Coulomb fitting basis sets: design and accuracy for systems containing H to Kr.
复制标题
自动生成的库仑拟合基组：包含 H 至 Kr 的系统的设计和精度。
DOI：
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发表时间：
2007
影响因子：
4.4
通讯作者：
M. Frisch
中科院分区：
文献类型：
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作者：
Rui Yang;Alistair P. Rendell;M. Frisch
对于中等规模的化学体系，使用辅助基组（ABS）来拟合电荷密度提供了一种加速各种量子化学方法性能的有用手段。因此，许多努力已经投入到各种ABS的设计。本文探讨了一种全新的方法，其中ABS是基于所使用的特定轨道基集（OBS）动态创建的。新方法包括用于将候选拟合函数合并在一起的参数，但是该参数也可以用于对ABS中的函数的数量提供一些粗粒度控制。系统地研究了新的自动生成ABS（auto-ABS）的精度为各种小系统包含元素H-Kr。在库仑能量计算使用自动ABS和各种OBS的误差被证明是小的误差相比，在哈特里-福克能量由于不完整的OBS。在固定大小的ABS相比，使用自动ABS的OBS的大小（质量）的扩展导致更小的误差。还将自动ABS的性能与最近提出的通用拟合集[Weigend，Phys.Chem.Chem.Phys.8，1057（2006）]的使用进行了比较，所述通用拟合集用于包含从H到Kr的原子的180种化合物。
For intermediate sized chemical systems the use of an auxiliary basis set (ABS) to fit the charge density provides a useful means of accelerating the performance of various quantum chemical methods. As a consequence much effort has been devoted to the design of various ABSs. This paper explores a fundamentally new approach where the ABS is created dynamically based on the specific orbital basis set (OBS) being used. The new approach includes a parameter that is used to coalesce candidate fitting functions together but which can also be used to provide some coarse grain control over the number of functions in the ABS. The accuracy of the new automatically generated ABS (auto-ABS) is systemically studied for a variety of small systems containing the elements H-Kr. Errors in the Coulomb energy computed using auto-ABS and with a variety of OBSs are shown to be small compared to errors in the Hartree-Fock energy due to incompleteness in the OBS. In contrast to fixed size ABSs, the use of auto-ABS is shown to lead to smaller errors as the size (quality) of the OBS is expanded. The performance of auto-ABS is also compared with the use of the recently proposed universal fitting sets [Weigend, Phys. Chem. Chem. Phys. 8, 1057 (2006)] for 180 compounds containing atoms from H to Kr.