计算C6色散系数的距离分离含时密度泛函理论的评价
Assessment of range-separated time-dependent density-functional theory for calculating C6 dispersion coefficients
摘要：
我们评估的线性响应范围分离的时间依赖的密度泛函理论（TDDFT）的变体，结合长程Hartree-Fock（HF）交换核与短程绝热交换相关核的局域密度近似（LDA）计算各向同性C6的色散系数的同二聚体的一些闭壳层原子和小分子。这种范围分离的TDDFT往往会低估小分子的C6系数，平均绝对百分比误差约为5%，比绝热LDA中的标准TDDFT略有改善，其往往会高估它们，平均绝对百分比误差为8%，但接近于时间依赖的Hartree-Fock，平均绝对百分比误差约为6%。因此，这些结果表明，在TDDFT中引入长程HF交换对C6系数的值具有较小但有益的影响。它也证实了本变体的距离分离TDDFT是一个相当准确的方法，即使只使用LDA型密度泛函，而不添加显式处理长程相关。
英文摘要：
We assess a variant of linear-response range-separated time-dependent density-functional theory (TDDFT), combining a long-range Hartree-Fock (HF) exchange kernel with a short-range adiabatic exchange-correlation kernel in the local-density approximation (LDA) for calculating isotropic C6 dispersion coefficients of homodimers of a number of closed-shell atoms and small molecules. This range-separated TDDFT tends to give underestimated C6 coefficients of small molecules with a mean absolute percentage error of about 5%, a slight improvement over standard TDDFT in the adiabatic LDA which tends to overestimate them with a mean absolute percentage error of 8%, but close to time-dependent Hartree-Fock which has a mean absolute percentage error of about 6%. These results thus show that introduction of long-range HF exchange in TDDFT has a small but beneficial impact on the values of C6 coefficients. It also confirms that the present variant of range-separated TDDFT is a reasonably accurate method even using only a LDA-type density functional and without adding an explicit treatment of long-range correlation.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
