Jacob Christoph R, Wesolowski Tomasz A, Visscher Lucas
Department of Theoretical Chemistry, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
J Chem Phys. 2005 Nov 1;123(17):174104. doi: 10.1063/1.2107567.
The orbital-free frozen-density embedding scheme within density-functional theory [T. A. Wesolowski and A. Warshel, J. Phys. Chem. 97, 8050 (1993)] is applied to the calculation of induced dipole moments of the van der Waals complexes CO2...X (X = He, Ne, Ar, Kr, Xe, Hg). The accuracy of the embedding scheme is investigated by comparing to the results of supermolecule Kohn-Sham density-functional theory calculations. The influence of the basis set and the consequences of using orbital-dependent approximations to the exchange-correlation potential in embedding calculations are examined. It is found that in supermolecular Kohn-Sham density-functional calculations, different common approximations to the exchange-correlation potential are not able to describe the induced dipole moments correctly and the reasons for this failure are analyzed. It is shown that the orbital-free embedding scheme is a useful tool for applying different approximations to the exchange-correlation potential in different subsystems and that a physically guided choice of approximations for the different subsystems improves the calculated dipole moments significantly.
密度泛函理论中的无轨道冻结密度嵌入方案 [T. A. 韦索洛夫斯基和 A. 瓦尔舍尔，《物理化学杂志》97, 8050 (1993)] 被应用于计算范德华复合物 CO2...X（X = He、Ne、Ar、Kr、Xe、Hg）的诱导偶极矩。通过与超分子科恩 - Sham 密度泛函理论计算结果进行比较，研究了嵌入方案的准确性。考察了基组的影响以及在嵌入计算中使用与轨道相关的交换相关势近似的后果。发现在超分子科恩 - Sham 密度泛函计算中，不同的常见交换相关势近似无法正确描述诱导偶极矩，并分析了这种失败的原因。结果表明，无轨道嵌入方案是在不同子系统中应用不同交换相关势近似的有用工具，并且对不同子系统进行基于物理的近似选择可显著改善计算得到的偶极矩。
