Ab initio SCF

Price S L and Stone A J 1980 Evaluation of anisotropic model intermolecular pair potentials using an ab initio SCF-CI surface Moi. Phys. 40 805... 

Rinaldi D, M F Ruiz-Lopez and J L Rivail 1983. Ab Initio SCF Calculations on Electrostatically Solvate Molecules Using a Deformable Three Axes Ellipsoidal Cavity. Journal of Chemical Physics 78 834 838. 

You can use any ab initio SCF calculation and all the semi-empiri-cal methods, except Extended Hiickel, for molecular dynamics simulations. The procedures and considerations are similar for simulations using molecular mechanics methods (see Molecular Dynamics on page 69). 

Irradiation of ethyleneimine (341,342) with light of short wavelength ia the gas phase has been carried out direcdy and with sensitization (343—349). Photolysis products found were hydrogen, nitrogen, ethylene, ammonium, saturated hydrocarbons (methane, ethane, propane, / -butane), and the dimer of the ethyleneimino radical. The nature and the amount of the reaction products is highly dependent on the conditions used. For example, the photoproducts identified ia a fast flow photoreactor iacluded hydrocyanic acid and acetonitrile (345), ia addition to those found ia a steady state system. The reaction of hydrogen radicals with ethyleneimine results ia the formation of hydrocyanic acid ia addition to methane (350). Important processes ia the photolysis of ethyleneimine are nitrene extmsion and homolysis of the N—H bond, as suggested and simulated by ab initio SCF calculations (351). The occurrence of ethyleneimine as an iatermediate ia the photolytic formation of hydrocyanic acid from acetylene and ammonia ia the atmosphere of the planet Jupiter has been postulated (352), but is disputed (353). 

A series of calculations on defect centers induced by radiation damage in alpha-quartz is reported. Ab initio SCF-MO calculations were carried out on a 21 atom cluster, Si50i6 % surrounded by 956 point-ions, designed to simulate alpha-quartz. This two-region approach made it possible to represent the long-range electrostatic effects, present in the crystal, in the SCF-MO cluster. 

A comprehensive review of the preparation, reactions, and n.m.r. spectra of phosphorus-fluorine compounds has appeared. This year s literature has been notable for the first detailed applications of ab initio SCF-MO calculations to the problems of bonding in halogenophosphines and their derivatives. - Comparison of the results of such theoretical calculations with experimental data obtained from photoelectron spectra shows a good correlation in the case of phosphorus trichloride and phosphoryl chloride, and of phosphorus trifluoride and its borane complex. ... 

There is ample evidence [9,17,44] that the INDO SCF procedure transformed according to this scheme (C INDO) can provide predictions comparable to those of minimal-basis-set ab initio SCF calculations for conformations and rotational barriers of conjugated molecules in the ground state. 

The ESR spectrum of methanesulfinyl radical (CH3SO), identified in a y-irradiated single crystal of dimethyl sulfoxide , indicates that the unpaired electron resides essentially (72%) on the sulfur 3p orbital with modest population on the sulfur 3s (0.65%) A detailed analysis of the temperature dependence leads to 2.6 kcal mol barrier height for the hindered internal rotation of the methyl group. At low temperature (88 K) the radical adopts a fixed conformation in which one proton lies in the nodal plane of the sulfur 3p orbital however, it was not possible to distinguish either experimentally or by ab initio SCF-MO calculations between the two possible conformations, that is, 2 and 3. 

Karlstrom G, Linse P, Wallqvist A, Johnson B. Intermolecular potential for the H20-C6H6 and the C6H6-C6H6 system calculated in an ab initio SCF Cl approximation. J Am Chem Soc 1983 105 3777-3782. 

Gresh N, Claverie P, Pullman A (1984) Theoretical studies of molecular conformation. Derivation of an additive procedure for the computation of intramolecular interaction energies. Comparison with ab initio SCF computations. Theor Chim 66(l) l-20... 

Espinosa, E., C. Lecomte, N. E. Ghermani, J. Devemy, M. M. Rohmer, M. Benard, and E. Molins. 1996. Hydrogen Bonds First Quantitative Agreement between Electrostatic Potential Calculations from Experimental X-(X+N) and Theoretical Ab Initio SCF Models. J. Am Chem. Soc. 118, 2501. 

Laurence, P. R., and C. Thomson. 1981. A Comparison of the Results of PCILO and Ab Initio SCF Calculations for the Molecules Glycine, Cysteine and N-Acetyl-Glycine. Theoret. Chim. Acta (Berl.) 58, 121-124. 

Voogd, J., J. L. Derissen, and F. B. van Duijneveldt. 1981. Calculation of Proton-Transfer Energies and Electrostatic Lattice Energies of Various Amino Acids and Peptides Using CNDO/2 and Ab Initio SCF Methods. J. Am. Chem. Soc. 103, 7701-7706. 

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