论文标题
有效的密度拟合显式相关的分散和交换色散能
Efficient density-fitted explicitly correlated dispersion and exchange dispersion energies
论文作者
论文摘要
适应对称的扰动理论（SAPT），$ e^{（20）} _ {\ rm disp} $和$ e^{（20）} _ {\ rm Inffer-disp} $中的前阶分散和交换分散项，$ e^{（20）} _ {\ rm disp} $和$ e^{（20）} _ {\ rm Exchand-disp} $。为了缓解此问题，最近提出了最近提出的，最近提出了这些更正的这些校正的变体，$ e^{（20）} _ {\ rm disp} $ - f12和$ e^{（20）} _ {\ rm fack-disp} $ - f12。然而，原始形式主义（M. Kodrycka等人，J。Chem。理论计算。2019，15，5965-5986）虽然在改善融合方面非常成功，但由于需要操纵几种两种两电子整体的基于常规轨道的SAPT，但对基于常规轨道的SAPT的竞争并没有竞争。在这项工作中，我们通过使用强大的密度拟合分解所有类型的两电子积分来消除这种需求。我们证明，当采用标准辅助碱（例如Aug-CC-PVXZ/MP2FIT）时，密度拟合近似的误差可以忽略不计。 The new implementation allowed us to study all complexes in the A24 database in basis sets up to aug-cc-pV5Z, and the $E^{(20)}_{\rm disp}$-F12 and $E^{(20)}_{\rm exch-disp}$-F12 values exhibit vastly improvement basis set convergence over their conventional counterparts.结合良好的$ e^{（20）} _ {\ rm disp} $ - f12和$ e^{（20）} _ {\ rm Exch-disp} $ - F12数字可以代替常规$ e^{（20）} _ {\ rm {\ rm {\ rm e^{\ rm e^{在任何级别的总SAPT相互作用能量计算中，Exch-disp} $一个（SAPT0，SAPT2+3，...）。我们表明，添加F12项并不能提高低级SAPT处理的准确性。但是，当理论误差以SAPT2+3（CCD）$δ$ MP2等高级SAPT方法最小化时，由于F12处理，基本设置的不完全误差的降低显着提高了小型基础计算的准确性。
The leading-order dispersion and exchange-dispersion terms in symmetry-adapted perturbation theory (SAPT), $E^{(20)}_{\rm disp}$ and $E^{(20)}_{\rm exch-disp}$, suffer from slow convergence to the complete basis set limit. To alleviate this problem, explicitly correlated variants of these corrections, $E^{(20)}_{\rm disp}$-F12 and $E^{(20)}_{\rm exch-disp}$-F12, have been proposed recently. However, the original formalism (M. Kodrycka et al., J. Chem. Theory Comput. 2019, 15, 5965-5986), while highly successful in terms of improving convergence, was not competitive to conventional orbital-based SAPT in terms of computational efficiency due to the need to manipulate several kinds of two-electron integrals. In this work, we eliminate this need by decomposing all types of two-electron integrals using robust density fitting. We demonstrate that the error of the density fitting approximation is negligible when standard auxiliary bases such as aug-cc-pVXZ/MP2FIT are employed. The new implementation allowed us to study all complexes in the A24 database in basis sets up to aug-cc-pV5Z, and the $E^{(20)}_{\rm disp}$-F12 and $E^{(20)}_{\rm exch-disp}$-F12 values exhibit vastly improvement basis set convergence over their conventional counterparts. The well-converged $E^{(20)}_{\rm disp}$-F12 and $E^{(20)}_{\rm exch-disp}$-F12 numbers can be substituted for conventional $E^{(20)}_{\rm disp}$ and $E^{(20)}_{\rm exch-disp}$ ones in a calculation of the total SAPT interaction energy at any level (SAPT0, SAPT2+3, ...). We show that the addition of F12 terms does not improve the accuracy of low-level SAPT treatments. However, when the theory errors are minimized in high-level SAPT approaches such as SAPT2+3(CCD)$δ$MP2, the reduction of basis set incompleteness errors thanks to the F12 treatment substantially improves the accuracy of small-basis calculations.
