Pair Density Shannon Information Measures and Their N‐Dependent Behavior in Diatomic Molecular Systems
Saúl J. C. Salazar, J. Antonio Zárate, J. M. Solano‐Altamirano, Humberto G. Laguna, Julio M. Hernández‐Pérez, Robin P. SagarABSTRACT
Pair density Shannon entropies and mutual information in position and in momentum space are calculated for two series of homonuclear and heteronuclear diatomic molecules using Hartree–Fock wave functions. The pair density entropy sum increases with the quality of the basis set. Mutual information, a measure of statistical correlation, is seen to be smaller in momentum space as compared to position space. The interpretation is that the momentum pair density is closer than the position pair density to a Hartree‐like reference. The ‐dependent behaviors of the entropy and mutual information sums are examined by fitting the data to three different model behaviors. Results show that these models are capable of representing the molecular data in differing degrees. The parameters obtained from a particular model are relatively constant across different chemical series. This adds evidence to the argument of a universal ‐dependent behavior of the entropy sums.