One-electron images in real space: Natural adaptive orbitals

• Published in: Journal of computational chemistry Vol. 36; no. 11; pp. 833 - 843
• Main Authors: Menéndez, Marcos, Álvarez Boto, Roberto, Francisco, Evelio, Martín Pendás, Ángel
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 30.04.2015; Wiley Subscription Services, Inc
• Subjects: Bonding indices; Chemical bonding; Chemical bonds; Chemistry; Correlation analysis; Electrons; one-electron function; Quantum Theory of Atoms in Molecules; Wave function analyses; one-electron function; Bonding indices; Chemical bonding; Wave function analyses; Quantum Theory of Atoms in Molecules
• ISSN: 0192-8651; 1096-987X
• DOI: 10.1002/jcc.23861

We introduce a general procedure to construct a set of one‐electron functions in chemical bonding theory, which remain physically sound both for correlated and noncorrelated electronic structure descriptions. These functions, which we call natural adaptive orbitals, decompose the n‐center bonding indices used in real space theories of the chemical bond into one‐electron contributions. For the n = 1 case, they coincide with the domain natural orbitals used in domain‐averaged Fermi hole analyses. We examine their interpretation in the two‐center case, and show how they behave and evolve in simple cases. Orbital pictures obtained through this technique converge onto the chemist's molecular orbital toolbox if electron correlation may be ignored, and provide new insight if it may not. © 2015 Wiley Periodicals, Inc. A hierarchical set of one‐electron functions called natural adaptive orbitals (NAdOs) is introduced. n‐Center NAdOs decompose real space n‐center bonding indices into one‐electron contributions. NAdOs maintain their meaning both for correlated and noncorrelated descriptions.