molecular orbital theory

(redirected from Mo theory)

molecular orbital theory,

detailed explanation of how electrons are distributed in stable moleculesmolecule
[New Lat.,=little mass], smallest particle of a compound that has all the chemical properties of that compound. A single atom is usually not referred to as a molecule, and ionic compounds such as common salt are not made up of molecules.
..... Click the link for more information.
. In the simpler valence theory of the chemical bondchemical bond,
mechanism whereby atoms combine to form molecules. There is a chemical bond between two atoms or groups of atoms when the forces acting between them are strong enough to lead to the formation of an aggregate with sufficient stability to be regarded as an
..... Click the link for more information.
, each atomatom
[Gr.,=uncuttable (indivisible)], basic unit of matter; more properly, the smallest unit of a chemical element having the properties of that element. Structure of the Atom
..... Click the link for more information.
 in a molecule is assumed to retain its own electrons. Even when electrons are shared, as in the covalent bond, it is possible to identify which electron came from which atom. The molecular orbital theory, however, treats each electron as associated with the molecule as a whole. Just as a free atom has certain allowed electron orbits and energies, each molecule has its own allowed molecular orbitals. The orbitals give the probability of finding the electron at any point in space. Each orbital can hold a maximum of two valence electrons and the structure of the molecule is built up by filling the lowest energy orbitals first. The calculations involved are extremely complex, and only the simplest molecules can be treated exactly.
References in periodicals archive ?
Goddard III of Caltech in Pasadena, combines the computational ease of the MO theory with the conceptual clarity of the VB theory, Messmer says.
From 1981-1992, the main focus of his research was on valence bond theory and its relationship to MO theory, and during that time, he developed a general model of reactivity based on a blend of VB and MO elements.
A Brief Story of VB Theory, Its Rivalry With MO Theory, Its Demise And Resurgence.
Origins of MO Theory and the Roots of VB-MO Rivalry.
His research focuses on electronic structure and spectra of heavy metal complexes; electronic and magnetic circular dichroism spectroscopy; and symmetry and MO theory.