Search

We show via Wigner functions how the sum and difference between Shannon entropies in position and in momentum space are related to conditional entropies, and how these quantities are linked to position-momentum correlations. The connection between Fermi, Coulomb and position-momentum correlations on these quantities is made, and the impact of these are discussed in atomic systems. [ABSTRACT FROM AUTHOR]

Shannon entropies of one- and two-electron atomic structure factors in the position and momentum representations are used to examine the behaviour of the off-diagonal elements of density matrices with respect to the uncertainty principle and to analyse the effects of radial correlation on off-diagonal order. We show that radial correlation induces off-diagonal order in position space which is characterized by larger entropic values. Radial correlation in momentum space is characterized by smaller entropic values as information is forced into regions closer to the diagonal. Related off-diagonal correlation functions are also discussed. [ABSTRACT FROM AUTHOR]

The asymptotic behaviour of the negative ratio of the density gradient to the electron density, q(r), for neutral and singly charged atoms has been investigated. The results show that, for large r, q(r) can approach its limit √8ε, where ε is the first ionization potential, from either above or below depending on the specific system considered. [ABSTRACT FROM AUTHOR]