title: Hybrid ab initio VB/MM method--a valence bond ride through classical landscapes.
abstract: The development of a new hybrid (QM/MM) method, where the QM part is treated by ab initio valence bond (VB) theory is presented. This VB/MM method has the advantages of empirical VB (EVB) methodology but does not rely on empirical parameterization for the quantum part. The method implements embedding of the quantum region of each diabatic state separately, by treating the electrostatic interactions between QM and MM regions classically. Additionally, it assumes that changes of the off diagonal matrix element due to different environments are such that the overall resonance integral does not change. These assumptions are discussed in detail and the validity of the method is shown to be successful in three different bond dissociation processes, where bond dissociation as well as solvation energies compare very well with the experimental data.
authors.affiliation: Department of Medicinal Chemistry and Natural Products, Lise Meitner-Minerva Center for Computational Quantum Chemistry, School of Pharmacy, The Hebrew University of Jerusalem, Jerusalem 91120, Israel. avital@md.huji.ac.il
authors.forename: Avital
authors.initials: A
authors.lastname: Shurki
authors.forename: Hadar A
authors.initials: HA
authors.lastname: Crown
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D005459:Fluorides / Q000737:chemistry; D006845:Hydrocarbons, Fluorinated / Q000737:chemistry; D007477:Ions; D008094:Lithium / Q000737:chemistry; D008956:Models, Chemical; D011789:Quantum Theory; D012996:Solutions / Q000737:chemistry*; D055672:Static Electricity; D020002:tert-Butyl Alcohol / Q000737:chemistry
chemical_list: D006845:Hydrocarbons, Fluorinated; D007477:Ions; D012996:Solutions; C029999:fluoromethane; D008094:Lithium; D020002:tert-Butyl Alcohol; D005459:Fluorides