Orbit Studies

Flehre W J, Ditchfieid R and Popie J A 1972 Self-consistent molecular-orbital methods XII. Further extension of Gaussian-type basis sets for use in molecular orbital studies of organic molecules J. Chem. Phys. 56 2257-61 Flariharan P C and Popie J A 1973 The influence of polarization functions on molecular orbital hydrogenation energies Theoret. Chim. Acta. 28 213-22... 

Shephard M J and Paddon-Row M N 1996 Conformational analysis of Cgg ball and chain molecules a molecular orbital study Aust. J. Chem. 49 395-403... 

Structure. The straiued configuration of ethylene oxide has been a subject for bonding and molecular orbital studies. Valence bond and early molecular orbital studies have been reviewed (28). Intermediate neglect of differential overlap (INDO) and localized molecular orbital (LMO) calculations have also been performed (29—31). The LMO bond density maps show that the bond density is strongly polarized toward the oxygen atom (30). Maximum bond density hes outside of the CCO triangle, as suggested by the bent bonds of valence—bond theory (32). The H-nmr spectmm of ethylene oxide is consistent with these calculations (33). 

Self-Consistent Molecular-Orbital Methods IX. An Extended Gaussian-Type Basis for Molecular-Orbital Studies of Organic Molecules R. Ditchfield, W. J. Hehre and J. A. Pople The Journal of Chemical Physics 54 (1971) 724-728... 

Hehre, W. J., Ditchfield, R., Pople, J. A., 1972, Self-Consistent Molecular Orbital Methods. XII. Further Extensions of Gaussian-Type Basis Sets for Use in Molecular Orbital Studies of Organic Molecules J. Chem. Phys., 56, 2257. 

Depke, G., N. Heinrich, and H. Schwarz. 1984. On the Gas Phase Chemistry of Ionize Glycine and Its Enol. A Combined Experimental and Ab Initio Molecular Orbital Study. Int. J. Mass Spectrom. Ion Porcesses 62, 99-117. 

Kleier, D. A., and W. N. Lipscomb. 1977. Molecular Orbital Study of Polypeptides. Conformational and Electronic Structure of Polyglycine. Int. J. Quantum Chem. Quantum Biol. Symp. 4, 73-86. 

Nakagawa, S., and H. Umeyama. 1981. Molecular Orbital Study of the Effects of Ionic Amino Acid Residues on Proton Transfer Energetics in the Active Site of Carboxypeptidase A. Chem. Phys. Letters 81, 503-507. 

Van Duijnen, P. T., and B. T. Thole. 1982. Cooperative Effects in ot-Helices An Ab Initio Molecular-Orbital Study. Biopolymers 21, 1749-1761. 

Furukawa and co-workers conducted an ab initio molecular orbital study of dications of 1,5-dichalcogenacycloocatanes <2000HAC31>. Nenaidenko and co-workers performed ab initio calculations with the HF/6-31G approximation on 1,4-dithiane 114 and a series of disulfonium dications, 115-118 <2003RCB1667>. The bond lengths and interatomic distances in the optimized structures are given in Table 20. 

Carbene Complex Geometries. Molecular orbital studies of the various conformations of several transition metal-carbene complexes have been undertaken by the groups of Fenske and Hoffmann (8,13). Of the two... 

Koga, N., and K. Morokuma, Ab initio molecular orbital studies of catalytic elementary reactions and catalytic cycles of transition-metal complexes. Chem. Rev., 91, 823-842 (1991). 

Sayre, R., Harlos, J. P., Rein, R., in Molecular orbital studies in chemical pharmacology (L. B. Kier, ed.), pp. 207—237, Springer-Verlag New York, Inc. Berlin-Heidelberg-New York Springer 1970. 

There is an equilibrium between the dimer and monomer, and molecular orbital study suggests that the heterochiral dimer is more stable than the homochiral isomer. The existence and behavior of the dimeric species were well confirmed by experiments such as cryoscopic molecular weight and NMR measurement. In the NMR study of a DAIB-catalyzed dialkylzinc addition reaction, noticeable changes were observed in the spectrum of the homochiral dimer on the addition of benzaldehyde, while the spectrum of the heterochiral complex remained the same. This may imply that the heterochiral complex is very stable and does not react, and the homochiral dimer leads to the reaction product. 

Green, J. P., and Kang, S. (1970) The correlation of electronic structures of indole derivatives with their biological activities. In Molecular Orbital Studies in Chemical Pharmacology, edited by L. B. Kier, pp. 105-120. Springer-Verlag, New York. 

Pullman, B., Courriere, P., and Berthod, H. (1974) Molecular orbital studies on the conformation of hallucinogenic indolealkylamines and related compounds. The isolated molecules and the solvent effect. J. Med. Chem.. 17 439-447. 

Rauhut, G. and Clark, T. Molecular orbital studies of electron-transfer reactions, J.Chem.Soc.,... 

F. H. Allen, J. P. M. Lommerse, V. J. Hoy J. A. K. Howard, G. R, Desiraju, The halogen—O(nitro) supramolecular synthon in crystal engineering a combined crystallographic database and ab initio molecular orbital study , Acta CrystaUogr, Section B, 1997, 53,1006-1016. 

Morokuma, K. 1971. Molecular orbital studies of hydrogen bonds. III. C = O- H — O hydrogen bond in H2CO- H20 and H2CO- -2H20. J. Chem. Phys. 55 1236. 

De Benedetti, P.G., Menziani, M.C., Rastelli, G. and Cocchi, M. (1991) Molecular orbital study of the basicity of prasozin analogues in relation to their a-adrenoceptor binding affinity. Journal of Molecular Structure (Theochem), 233, 343-351. 

A tentative correlation between the population of specific conformers about the 1, 2-carbon-carbon bond and i.s.a. has emerged in a preliminary molecular orbital study on a series of ortho-substituted phenoxypropanolamines (15)... 

The general approach is illustrated in detail for the case of aqueous ferrous and ferric ions, and the calculated rate constant and activation parameters are found to be in good agreement with the available experimental data. The formalisms we have employed in studying such complicated condensed phase processes necessarily rely on numerous approximations. Furthermore, some empirical data have been used in characterizing the solvated ions. We emphasize, nevertheless, that (1) none of the parameters were obtained from kinetic data, and (2) this is, as far as we are aware, the first such theoretical determination to be based on fully Ab initio electronic matrix elements, obtained from large scale molecular orbital (MO) calculations. A molecular orbital study of the analogous hexaaquo chromium system has been carried out by Hush, but the calculations were of an approximate, semi-empirical nature, based in part on experi-... 

A theoretical approach in molecular orbital studies to formulate an expression for the wave function of a molecular orbital (both for bonding and antibonding orbitals) by linear combinations of the overlapping atomic orbitals with appropriate weighting factors. 

Monofluorinated Analogues of Polybrominated Diphenyl Ethers as Analytical Standards Synthesis, NMR, and GC-MS Characterization and Molecular Orbital Studies (from Luthe et al., 2006)... 

Luthe, G. Leonards, P. E. G. Reijerink, G. S. Liu, H. Johansen, J. E. Robertson, L. W. Monofluorinated Analogues of Polybrominated Diphenyl Ethers as Analytical Standards Synthesis, NMR, and GC-MS Characterization and Molecular Orbital Studies. Environ. Sci. Technol. 2006, 40, 3023-3029. 

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