{"doi":"10.1063/1.472933","title":"Rationale for mixing exact exchange with density functional approximations","abstract":"<jats:p>Density functional approximations for the exchange-correlation energy EDFAxc of an electronic system are often improved by admixing some exact exchange Ex: Exc≊EDFAxc+(1/n)(Ex−EDFAx). This procedure is justified when the error in EDFAxc arises from the λ=0 or exchange end of the coupling-constant integral ∫10 dλ EDFAxc,λ. We argue that the optimum integer n is approximately the lowest order of Görling–Levy perturbation theory which provides a realistic description of the coupling-constant dependence Exc,λ in the range 0≤λ≤1, whence n≊4 for atomization energies of typical molecules. We also propose a continuous generalization of n as an index of correlation strength, and a possible mixing of second-order perturbation theory with the generalized gradient approximation.</jats:p>","journal":"The Journal of Chemical Physics","year":1996,"id":6230,"datarank":15.641854211037325,"base_score":8.782322859397507,"endowment":8.782322859397507,"self_citation_contribution":1.3173484289096262,"citation_network_contribution":14.324505782127698,"self_endowment_contribution":1.3173484289096262,"citer_contribution":14.324505782127698,"corpus_percentile":89.1,"corpus_rank":1818,"citation_count":6517,"citer_count":183,"citers_with_citation_signal":183,"citers_with_endowment":183,"datacite_reuse_total":0,"is_dataset":false,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"1996-12-08","authors":[{"id":28864,"name":"Matthias Ernzerhof","orcid":"0000-0001-5679-8902","position":1,"is_corresponding":false},{"id":58315,"name":"Kieron Burke","orcid":"0000-0002-6159-0054","position":2,"is_corresponding":false},{"id":5717,"name":"John P. Perdew","orcid":"0000-0003-4237-824X","position":0,"is_corresponding":true}],"reference_count":57,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-03-01T18:20:47.508186Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}