2022-05-27T22:28:57Zhttps://nagoya.repo.nii.ac.jp/oaioai:nagoya.repo.nii.ac.jp:000070692021-03-01T12:28:35ZLocal Approximation of the Correlation Energy Functional in the Density Matrix Functional TheoryYasuda, KojiCopyright: American Physical Society, All rights reserved.A local approximation formula of the correlation energy functional Ec in terms of the first-order reduced density matrix (1-RDM) is presented. With the contracted Schrödinger equation the principal dependence of Ec on the natural occupation numbers ni is identified. Using the effective mass theory, Ec is expressed as a functional of the local density and the local variable, J = Σi√ni(1-ni)|Φi|2 , where Φi are the natural spin orbitals. This local approximation satisfies the homogeneous coordinate scaling relation, gives the exact result for a one-electron system, and is almost free from the exchange energy error. It reproduced about 90% of the correlation energies of atoms and molecules.American Physical Society2002-02-04engjournal articlehttp://hdl.handle.net/2237/8743https://nagoya.repo.nii.ac.jp/records/7069http://dx.doi.org/10.1103/PhysRevLett.88.053001PHYSICAL REVIEW LETTERS885053001053001https://nagoya.repo.nii.ac.jp/record/7069/files/PhysRevLett_88-53001.pdfapplication/pdf83.8 kB2018-02-19