Orbitally resolved charge sensitivity analysis: Basic concepts and relations

摘要: Following the recent developments of charge sensitivity analysis (CSA) in atoms-in-molecules (AIM) resolution, corresponding CSA quantities orbital (or shell) resolution (OR) are defined. The ORelectron population variables, ordinary closed-shell SCF problem, elements bond-order matrix P, and their conjugates, “chemical potentials,” FT = ∂E/∂P, respective Fock elements, appropriate for representation question; here E is energy. second derivatives ∂2E/∂P∂P define ORhardness tensor from which all related OR CSs, e.g., hardness, softnesses, Fukui function (FF) indices, etc., can be determined. rigid potentials hardness tensor, to “frozen” approximation, examined more detail, decoupled normal orbitals (NoO) introduced, becomes diagonal. Illustrative valence-shell NoO contours water molecule given discussed. new approximation FF as occupation probabilities, proposed on basis density functional development Donnely Parr natural orbitals, relevant expressions molecular fragment (collection orbitals) summarized.