English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

A procedure has been proposed to construct numerically the exchange‐correlation exc(r) and correlation ec(r) energy densities of density functional theory using the correlated first‐ and second‐order density matrices from ab initio calculations. ec(r) as well as its kinetic and potential components have been obtained for the two‐electron He atom and H2 molecule. The way various correlation effects manifest themselves in the form of ec(r) has been studied. The ec(r) have been compared with some density functional local and gradient‐corrected models ecmod(r). The investigation of the shape of the model energy densities ecmod(r) has been extended to the Be2 and F2 molecules and the corresponding correlation energies Ec have been calculated and discussed for a number of atomic and molecular systems. The results show the importance of a proper modeling of ec(r) in the molecular bond midpoint region.

Correlation energy density from ab initio first- and second-order density matrices: A benchmark for approximate functionals