Electron number distribution functions with iterative Hirshfeld atoms

Electron number distribution functions (EDF) for the fuzzy domains of the recently defined iterative Hirshfeld or stockholder atoms are considered for the first time. We obtain these EDFs for a set of test molecules and compare them to those coming from other fuzzy (standard Hirshfeld) and exhaustive (Quantum Theory of Atoms in Molecules) partitionings of the real space. Our results show that iterative Hirshfeld EDFs are clearly better than the ones obtained with the standard Hirshfeld partitioning. However, due to the overlapping character of the self-consistent Hirshfeld densities, the highly ionic resonant structures are less populated than in the QTAIM EDFs. Electron correlation effects on the EDFs are also briefly discussed.