Maximum probability domains from Quantum Monte Carlo calculations

✍ Scribed by Anthony Scemama; Michel Caffarel; Andreas Savin

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 588 KB
• Volume: 28
• Category: Article
• ISSN: 0192-8651
• DOI: 10.1002/jcc.20526

✦ Synopsis

Abstract

Although it would be tempting to associate the Lewis structures to the maxima of the squared wave function |Ψ|^2^, we prefer in this paper the use of domains of the three‐dimensional space, which maximize the probability of containing opposite‐spin electron pairs. We find for simple systems (CH~4~, H~2~O, Ne, N~2~, C~2~H~2~) domains comparable to those obtained with the electron localization function (ELF) or by localizing molecular orbitals. The different domains we define can overlap, and this gives an interesting physical picture of the floppiness of CH and of the symmetric hydrogen bond in FHF^−^. The presence of multiple solutions has an analogy with resonant structures, as shown in the trans‐bent structure of Si~2~H~2~. Correlated wave functions were used (MCSCF or Slater‐Jastrow) in the Variational Quantum Monte Carlo framework. © 2006 Wiley Periodicals, Inc. J Comput Chem 28: 442–454, 2007