|Title:||Combining density-based dynamical correlation with a reduced-density-matrix strong-correlation description||Authors:||Van Meer R., Gritsenko O., Chai J.-D.
|Keywords:||Calculations; Curve fitting; Dissociation; Molecules; Potential energy; Quantum theory; Complete active space; Correlation corrections; Correlation energy; Density functionals; Dynamical correlations; Potential energy curves; Reduced-density matrix; Strong correlation; Density functional theory||Issue Date:||2020||Journal Volume:||102||Journal Issue:||3||Source:||Physical Review A||Abstract:||
A combined density and density-matrix functional method is proposed for the calculation of potential energy curves of molecular multibond dissociation. Its density-matrix part, a pair-density functional, efficiently approximates the ab initio pair density of the complete active space (CAS) method. The corresponding approximate on-top pair density Π is employed to correct for double counting in the correlation energy functional. The proposed ELS+ method, which augments the extended L?wdin-Shull (ELS) density-matrix functional with the Π-based scaled density functional, closely reproduces potential curves of the paradigmatic multibond dissociation in N2, H2O, and H2CO molecules calculated with the recently proposed CASΠDFT [CAS augmented with the Π-based scaled correlation correction of density functional theory (DFT)] method. Furthermore, with the additional correction for the intrafragment correlation between the broken-bond electrons, ELS++ reproduces well the benchmark potential curve of the N2 molecule by Lie and Clementi. ? 2020 American Physical Society.
|Appears in Collections:||物理學系|
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