Maximal orbital analysis of molecular wavefunctions. Issue 1 (18th September 2018)

• Record Type: Journal Article
• Authors: Dupuis, Michel; Nallapu, Meghana
• Other Names: Bowman Joel guestEditor.; Hirao Kimihiko guestEditor.; Musaev Jamal guestEditor.; Nakatsuji Hiroshi guestEditor.; Sakaki Shigeyoshi guestEditor.
• Is Part Of: Journal of computational chemistry. Volume 40:Issue 1(2019)
• Page Start: 39
• Page End: 50
• Publication Date: 2018-09-18
• Subjects: molecular wavefunction -- fragment orbitals -- decomposition -- corresponding orbital transformation; Chemistry -- Data processing -- Periodicals; 542.85
• DOI: 10.1002/jcc.25385
• Languages: English
• ISSNs: 0192-8651

Abstract

Abstract : We describe a new way to decompose one‐electron orbitals of a molecule into atom‐centered or fragment‐centered orbitals by an approach that we call " maximal orbital analysis " (MOA). The MOA analysis is based on the corresponding orbital transformation (COT) that has the unique mathematical property of maximizing any sub‐trace of the overlap matrix, in Hilbert metric sense, between two sets of nonorthogonal orbitals. Here, one set comprises the molecule orbitals (Hartree–Fock, Kohn–Sham, complete‐active‐space, or any set of orthonormal molecular orbitals), the other set comprises the basis functions associated with an atom or a group of atoms. We show in prototypical molecular systems such as a water dimer, metal carbonyl complexes, and a mixed‐valent transition metal complex, that the MOA orbitals capture very well key aspects of wavefunctions and the ensuing chemical concepts that govern electronic interactions in molecules. © 2019 Wiley Periodicals, Inc. Abstract : In the water dimer, MOA orbital #6 of the "donor" monomer looks like an OH(σ*) orbital and receives electron density from the "acceptor" monomer. The MOA orbitals of the "donor" water in the water dimer illustrate that hydrogen bonding is due to charge transfer from the "acceptor" water into the OH(σ*) orbital of the "donor" water.