Brütting Moritz, Bahmann Hilke, Kümmel Stephan
Theoretical Physics IV, University of Bayreuth, 95440 Bayreuth, Germany.
Physical and Theoretical Chemistry, University of Wuppertal, 42097 Wuppertal, Germany.
J Phys Chem A. 2024 Jul 4;128(26):5212-5223. doi: 10.1021/acs.jpca.4c02787. Epub 2024 Jun 21.
Some of the most successful exchange-correlation approximations in density functional theory are "hybrids", i.e., they rely on combining semilocal density functionals with exact nonlocal Fock exchange. In recent years, two classes of hybrid functionals have emerged as particularly promising: range-separated hybrids on the one hand, and local hybrids on the other hand. These functionals offer the hope to overcome a long-standing "observable dilemma", i.e., the fact that density functionals typically yield either a good description of binding energies, as obtained, e.g., in global and local hybrids, or physically interpretable eigenvalues, as obtained, e.g., in optimally tuned range-separated hybrids. Obtaining both of these characteristics from one and the same functional with the same set of parameters has been a long-standing challenge. We here discuss combining the concepts of local range separation and local hybrids as part of a constraint-guided quest for functionals that overcome the observable dilemma.
密度泛函理论中一些最成功的交换关联近似是“杂化泛函”，即它们依赖于将半局域密度泛函与精确的非局域福克交换相结合。近年来，两类杂化泛函已显得特别有前景：一类是范围分离杂化泛函，另一类是局域杂化泛函。这些泛函有望克服一个长期存在的“可观测量困境”，即密度泛函通常要么能很好地描述结合能（例如在全局和局域杂化泛函中得到的那样），要么能给出可从物理上解释的本征值（例如在优化调整的范围分离杂化泛函中得到的那样）。从具有相同参数集的同一个泛函中同时获得这两个特性一直是一个长期存在的挑战。我们在此讨论将局域范围分离和局域杂化的概念相结合，作为寻求克服可观测量困境的泛函的约束引导探索的一部分。
