TY - JOUR

T1 - On the separation of the information content of the Fermi and Coulomb holes and their influence on the electronic properties of molecular systems

AU - Rincon, Luis

AU - Javier Torres, F.

AU - Becerra, Marcos

AU - Liu, Shubin

AU - Fritsch, Alain

AU - Almeida, Rafael

N1 - Publisher Copyright:
© 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group.

PY - 2019/3/4

Y1 - 2019/3/4

N2 - In this paper, two information-based functions are employed as a real space measure of the Fermi and Coulomb holes for same-spin electrons. The first one is the information content of the Exchange-Correlation hole, calculated from the Kullback–Leibler divergence of the same-spin conditional pair density respect to the marginal probability (XXC). As reported previously, XXC, can be used to reveal the regions of the space associated to the classical electron pair model. Here, correlated wave-functions, such as CISD, MP2, and CCSD, are considered for the calculation of XXC. This is achieved by introducing an approximated method based on employing natural orbitals and their occupancy numbers. In addition to XXC, in this work we propose a measure of the information content of the same-spin correlation hole, which is computed in terms of the Kullback–Leibler divergence of a correlated same-spin conditional pair density respect to the uncorrelated Hartree–Fock pair density (XC). The proposed methodology is discussed in the light of the result derived from noble gas atoms, the (F 2 ) molecule and some non-covalently bonded systems.

AB - In this paper, two information-based functions are employed as a real space measure of the Fermi and Coulomb holes for same-spin electrons. The first one is the information content of the Exchange-Correlation hole, calculated from the Kullback–Leibler divergence of the same-spin conditional pair density respect to the marginal probability (XXC). As reported previously, XXC, can be used to reveal the regions of the space associated to the classical electron pair model. Here, correlated wave-functions, such as CISD, MP2, and CCSD, are considered for the calculation of XXC. This is achieved by introducing an approximated method based on employing natural orbitals and their occupancy numbers. In addition to XXC, in this work we propose a measure of the information content of the same-spin correlation hole, which is computed in terms of the Kullback–Leibler divergence of a correlated same-spin conditional pair density respect to the uncorrelated Hartree–Fock pair density (XC). The proposed methodology is discussed in the light of the result derived from noble gas atoms, the (F 2 ) molecule and some non-covalently bonded systems.

KW - Coulomb hole

KW - Electron localisation

KW - Fermi hole

KW - Kullback–Leibler divergence

KW - electron correlation

UR - http://www.scopus.com/inward/record.url?scp=85054571689&partnerID=8YFLogxK

U2 - 10.1080/00268976.2018.1530462

DO - 10.1080/00268976.2018.1530462

M3 - Artículo

AN - SCOPUS:85054571689

SN - 0026-8976

VL - 117

SP - 610

EP - 625

JO - Molecular Physics

JF - Molecular Physics

IS - 5

ER -