{"doi":"10.1002/qua.560340105","title":"A spin‐free form of valence bond theory","abstract":"<jats:title>Abstract</jats:title><jats:p>Classical valence bond theory is recast in a spin‐free form which provides a practicable route to ab initio calculations of molecular electronic structure. The approach is simple and direct and requires only efficient algorithms for the generation and processing of permutations and the handling of Rumer diagrams: it makes modest demands on computing power and pilot calculations have indeed been performed entirely within the fast memory of a personal computer, which should be sufficient for dealing with systems possessing up to 10 electrons outside a closed shell. Simple applications confirm the conclusion of Cooper et al. [1] that, by using strongly overlapping orbitals, a small number of classical (nonpolar) structures can give results close to those obtained in a “full <jats:sc>CI</jats:sc>” calculation.</jats:p>","journal":"International Journal of Quantum Chemistry","year":1988,"id":17187,"datarank":6.43963129979292,"base_score":4.77912349311153,"endowment":4.77912349311153,"self_citation_contribution":0.7168685239667295,"citation_network_contribution":5.72276277582619,"self_endowment_contribution":0.7168685239667295,"citer_contribution":5.72276277582619,"corpus_percentile":null,"corpus_rank":null,"citation_count":118,"citer_count":104,"citers_with_citation_signal":97,"citers_with_endowment":97,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":123814,"name":"Roy McWeeny","orcid":null,"position":0,"is_corresponding":false}],"reference_count":0,"raw_metadata":{"has_enrichment":true,"base_score":4.77912349311153,"endowment":4.77912349311153,"datacite_reuse_total":0,"file_count":0,"downloads":0,"views":0,"has_version_chain":false,"is_dataset":false,"is_oa":false,"pmid":"21071399","pmcid":null,"openalex_id":"https://openalex.org/W2055649238","authors":[],"funders":[],"total_grants":0,"fwci":2.7479,"citation_percentile":0.90253756,"influential_citations":0,"citation_trend":[{"year":2012,"count":1},{"year":2013,"count":4},{"year":2014,"count":3},{"year":2016,"count":1},{"year":2017,"count":1},{"year":2019,"count":1},{"year":2020,"count":1},{"year":2021,"count":1},{"year":2022,"count":2}],"oa_status":"closed","license":"http://onlinelibrary.wiley.com/termsAndConditions#vor","oa_locations":[{"url":"https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fqua.560340105","host_type":"publisher"},{"url":"https://onlinelibrary.wiley.com/doi/pdf/10.1002/qua.560340105","host_type":"publisher"},{"url":"https://doi.org/10.1002/qua.560340105","host_type":"journal"}],"fields_of_study":["Advanced Chemical Physics Studies","Catalysis and Oxidation Reactions","Crystallography and molecular interactions"],"mesh_terms":[],"keywords":["Valence bond theory","Generalized valence bond","Modern valence bond theory","Valence electron","Simple (philosophy)","Atomic orbital","Open shell","Valence (chemistry)","Electronic structure","Statistical physics","Spin (aerodynamics)","Electron","Physics","Quantum mechanics","Theoretical physics","Chemistry","Thermodynamics"],"sdg_mappings":[],"linked_datasets":[],"clinical_trials":[],"software_tools":[],"database_accessions":[],"source":"live","citation_network_status":"fetched"},"created_at":"2026-06-02T17:50:17.320597Z","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":[]}