Extended Huckel molecular orbital EHMO

The substrate in these studies was restricted to be rigid, and Morse functions were used for the hydrogen-surface and two-body interactions. The parameters in the Morse functions were determined for single hydrogen atoms adsorbed on the tungsten surface by fitting to extended Huckel molecular orbital (EHMO) results, and the H2 Morse parameters were fit to gas-phase data. The Sato parameter, which enters the many-body LEPS prescription, was varied to produce a potential barrier for the desorption of H2 from the surface which matched experimental results. 

The fact that the electrochemical oxidation of cis-[M2(cp)2(/x-SR)2(CO)4] and of [M2(/i-SR)2(CO)8]2 is reversible despite the amount of structural reorganization involved suggests that these changes require low activation energy. Extended Huckel Molecular Orbital (EHMO) calculations on the model complex (R = H) indicated that the Lowest Unoccupied Molecular Orbital (LUMO) was the u Mo—Mo [ 1- Weakening of the... 

Haskins (Ref 9c) has compared molecular orbital calcns of some azides and tetrazoles with expl behavior, dipole moments, and binding energies. He used an iterative extended Huckel molecular orbital approach to calculate dipole moments of l-(H)tetrazole, 2-(H)tetrazole, and 5-aminotetrazole and found good agreement with exptl measurements. For example, l-(H)tetra-zole was calculated as 5.269p and measured as 5,1 Ip. Binding energies calcd by the similar extended Huckel molecular orbital (EHMO)... 

FIGURE 35 Results of extended Huckel molecular orbital (EHMO) calculations for the isolated [ IrYellis] cluster complex in (IrYgllio and representation of the three highest occupied molecular orbitals. 

ECP (Effective Core Potential) 171 Effective pair potential 68 EHMO (Extended Huckel Molecular Orbital Model) 130 Eigenvalue 17 Eigenvector 17 Einstein relation 253 Electric dipole moment 100, 265, 282 Electric field gradient 278 Electric moments 184 Electric quadrupole moment 268, 269 Electric second moment 268 Electric susceptibility 256 Electron affinity 147 Electron correlation 186, 273 Electron density 100, 218, 222 Electron relaxation 118 Electron spin 91, 95, 99, 277, 305 Electronic Schrodinger equation 74 Electrostatic field 14 Electrostatic field gradient 271... 

EHMO extended Huckel molecular orbital (quantum chemical method)... 

Extended Huckel molecular orbital calculations were used to obtain an initial, qualitative picture of the electronic structure changes involved in two-electron transfer. EHMO calculations were carried out in D2h symmetry on H2P" bridged analogs of the [M2(p-PR2)2(CO)8] complexes using the CACAO program (50). Structural information and computational details are provided in reference 18. 

Extended Huckel Molecular Orbital calculations (EHMO) on the model compound with tetraazo porphin (TAP ) as the macrocycle and Fe as the central metal atom and the dianion of acetylene (C=C) as the bridging ligand indicate that the resulting 13 ai, crystal orbital of this polymer should be extremely concentrated along the central axis via the bridging ligand. The crystal orbital will be only partially filled and the polymer should exhibit metal-like conductivity along the one-dimensional chain [108,110]. 

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