title: Electron localization function as information measure.
abstract: The conditional two-electron probability function, which defines the electron localization function (ELF) of Becke and Edgecombe in the Kohn-Sham theory, is interpreted as the nonadditive (interorbital) Fisher information contained in the electron distribution. The probability normalization considerations suggest a use of the related information measure defined in terms of the unity-normalized probability distributions (shape factors of the electron densities), as the key ingredient of the modified information-theoretic ELF. This modified Fisher information density is validated by a comparison with the original two-electron probability function. Illustrative applications to typical molecular systems demonstrate the adequacy of the modified information-theoretic ELF in extracting the key features of the electron distributions in molecules. The overall Fisher information itself and the associated information-distance quantities are also proposed as complementary localization functions.
authors.affiliation: Faculty of Chemistry, Department of Theoretical Chemistry, Jagiellonian University, R. Ingardena 3, 30-060-Cracow, Poland. nalewajs@chemia.uj.edu.pl
authors.forename: Roman F
authors.initials: RF
authors.lastname: Nalewajski
authors.forename: Andreas M
authors.initials: AM
authors.lastname: Köster
authors.forename: Sigfrido
authors.initials: S
authors.lastname: Escalante