Longuet-Higgins* theory

The Longuet-Higgins theory based on Huckel MO theory and Hund s rule was pioneering work in the area of molecular design of high-spin alternant hydrocarbons and has been appreciated for its predictability. 

Detonation, LH Theory. See Detonation, Longuet-Higgins Theory... 

See also Detonation, Longuet-Higgins Theory and Detonation, Pseudopotential Theories... 

It is noticeable that the NRG theory developed here furnishes two different groups for the double rotation in planar pyrocatechin (or acetone), and the double rotation and wagging mode in non-planar pyrocatechin (or pyramidal acetone). The group structures, however, are seen to be the same. The Longuet-Higgins theory yields indeed the same Molecular Symmetry Groups for both pyramidal uid planar systems. As a result, the NRG theory is seen to furnish a more det ulled information about the dynamics of the non-rigid systems. 

Stillinger F 1973 Structure in aqueous solutions from the standpoint of scaled particle theory J. Solution Chem. 2 141 Widom B 1967 Intermolecular forces and the nature of the liquid state Sc/e/ ce 375 157 Longuet-Higgins H C and Widom B 1964 A rigid sphere model for the melting of argon Mol. Phys. 8 549... 

Using the statistical mechanical theory, Longuet-Higgins and Pople obtained a correlation function for the velocities in a liquid consisting of... 

The formulation and systematization of these rules came in a series of famous papers by Woodward and Hoffmann (8), whose arguments soon merged with the correlation diagram formalism of Longuet-Higgins and Abrahamson (9) into a now well accepted and far-reaching theory (10). 

Longuet-Higgins phase-based treatment, three-particle reactive system, 157-168 theoretical background, 43-44 observability, 208 quantum theory, 200 Phase-inverting reactions molecular model, 496-499 phase-change rule, pericyclic reactions, 449-450... 

Molecular Beams, Reactive Scattering in (Herschbach) Molecular Orbital Theory, Recent Developments in (Longuet-Higgins). ... 

Longuet-Higgins, H. C. Some Studies in Molecular Orbital Theory. I., II.,... 

In Hiickel theory, E is approximated as a sum of orbital energies, e say, computed just as if the electrons were independent. Coulson and Longuet-Higgins (1947a,b) showed that the total -electron energy in the ground state is then... 

We select without proof, from the theory of Coulson and Longuet-Higgins (1947a,b), those formulae which relate to quantities used in the description of chemical reactivity, as follows ... 

Conformal Solution (CS) Theories. See under Detonation, Longuet-Higgins (LH) Theory... 

The early developments in the chemistry of boron hydrides and aluminum alkyls quickly led to the realization that these species did not conform to the accepted theories of bonding, but required the development of new concepts that could account for the dimeric or polymeric nature of these derivatives. These concepts, were initially provided in a number of papers by Mulliken (88), Longuet-Higgins (70), Pitzer (93), Pitzer and Gutowsky (94), and Rundle (97, 98). Much of this work has been summarized recently in books by Wade (118), by Lipscomb (69),... 

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