Edson Rodrigues de Oliveira, Renato Pessoa, Ladir Cândido
{"title":"Electron correlation in benzene: A QMC study of neutral and charged states.","authors":"Edson Rodrigues de Oliveira, Renato Pessoa, Ladir Cândido","doi":"10.1063/5.0244421","DOIUrl":null,"url":null,"abstract":"<p><p>In this paper, we employ variational Monte Carlo and fixed-node diffusion Monte Carlo (FN-DMC) methods to investigate electron correlation effects in neutral and charged benzene molecules. Using orbitals from Hartree-Fock (HF) and density functional theory calculations, FN-DMC with the frozen-core approximation yields correlation energies consistent with CCSD(T) and ph-AFQMC, while all-electron FN-DMC lowers the correlation energy by ∼0.27 a.u., highlighting the role of core-electron contributions. On average, all-electron FN-DMC predicts vertical [VIP: 0.3477(34) a.u.] and adiabatic [AIP: 0.3433(39) a.u.] ionization potentials, both slightly above the experimental value [0.339 70(2) a.u.]. Zero-point vibrational energy (ZPVE) corrections adjust the VIP and AIP by -0.012 and +0.0037 a.u., respectively, improving agreement with experiment. Compared to HF, FN-DMC incorporates an additional 0.055 a.u. (≈1.5 eV) of correlation energy into the IP, demonstrating its effectiveness in capturing electron correlation in aromatic systems.</p>","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"162 12","pages":""},"PeriodicalIF":3.1000,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Chemical Physics","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1063/5.0244421","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
In this paper, we employ variational Monte Carlo and fixed-node diffusion Monte Carlo (FN-DMC) methods to investigate electron correlation effects in neutral and charged benzene molecules. Using orbitals from Hartree-Fock (HF) and density functional theory calculations, FN-DMC with the frozen-core approximation yields correlation energies consistent with CCSD(T) and ph-AFQMC, while all-electron FN-DMC lowers the correlation energy by ∼0.27 a.u., highlighting the role of core-electron contributions. On average, all-electron FN-DMC predicts vertical [VIP: 0.3477(34) a.u.] and adiabatic [AIP: 0.3433(39) a.u.] ionization potentials, both slightly above the experimental value [0.339 70(2) a.u.]. Zero-point vibrational energy (ZPVE) corrections adjust the VIP and AIP by -0.012 and +0.0037 a.u., respectively, improving agreement with experiment. Compared to HF, FN-DMC incorporates an additional 0.055 a.u. (≈1.5 eV) of correlation energy into the IP, demonstrating its effectiveness in capturing electron correlation in aromatic systems.
期刊介绍：
The Journal of Chemical Physics publishes quantitative and rigorous science of long-lasting value in methods and applications of chemical physics. The Journal also publishes brief Communications of significant new findings, Perspectives on the latest advances in the field, and Special Topic issues. The Journal focuses on innovative research in experimental and theoretical areas of chemical physics, including spectroscopy, dynamics, kinetics, statistical mechanics, and quantum mechanics. In addition, topical areas such as polymers, soft matter, materials, surfaces/interfaces, and systems of biological relevance are of increasing importance.
Topical coverage includes:
Theoretical Methods and Algorithms
Advanced Experimental Techniques
Atoms, Molecules, and Clusters
Liquids, Glasses, and Crystals
Surfaces, Interfaces, and Materials
Polymers and Soft Matter
Biological Molecules and Networks.
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
