Reine Simen, Tellgren Erik, Krapp Andreas, Kjaergaard Thomas, Helgaker Trygve, Jansik Branislav, Host Stinne, Salek Paweł
Centre of Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway.
J Chem Phys. 2008 Sep 14;129(10):104101. doi: 10.1063/1.2956507.
Density fitting is an important method for speeding up quantum-chemical calculations. Linear-scaling developments in Hartree-Fock and density-functional theories have highlighted the need for linear-scaling density-fitting schemes. In this paper, we present a robust variational density-fitting scheme that allows for solving the fitting equations in local metrics instead of the traditional Coulomb metric, as required for linear scaling. Results of fitting four-center two-electron integrals in the overlap and the attenuated Gaussian damped Coulomb metric are presented, and we conclude that density fitting can be performed in local metrics at little loss of chemical accuracy. We further propose to use this theory in linear-scaling density-fitting developments.
密度拟合是加速量子化学计算的一种重要方法。Hartree-Fock和密度泛函理论中的线性标度发展突出了对线性标度密度拟合方案的需求。在本文中，我们提出了一种稳健的变分密度拟合方案，该方案允许在局部度量中求解拟合方程，而不是像线性标度所要求的那样在传统的库仑度量中求解。给出了在重叠和衰减高斯阻尼库仑度量中拟合四中心双电子积分的结果，我们得出结论，密度拟合可以在局部度量中进行，而化学精度损失很小。我们进一步建议在线性标度密度拟合发展中使用该理论。
