Domain averaged Fermi hole analysis for open-shell systems.

The Article reports the extension of the new original methodology for the analysis and visualization of the bonding interactions, known as the analysis of domain averaged Fermi holes (DAFH), to open-shell systems. The proposed generalization is based on straightforward reformulation of the original approach within the framework of unrestricted Hartree-Fock (UHF) and/or Kohn-Sham (UKS) levels of the theory. The application of the new methodology is demonstrated on the detailed analysis of the picture of the bonding in several simple systems involving the doublet state of radical cation NH(3)((+)) and the triplet ground state of the O(2) molecule.