Pii: S0166-1280(99)00011-1

Pii: S0166-1280(99)00412-1

Local exchange-correlation functionals are defined for different systems with spherical symmetry, by requiring that they reproduce the correct exchange-correlation energy and exchange-correlation potential (up to a constant). For comparison, the results with the uniform electron gas local density approximation and a generalized gradient approximation are also shown. q 2000 Elsevier Science B.V....

Pii: S0734-9750(99)00011-7

Pii: S0166-1280(99)00047-0

Systematic computational studies of the XNO (X ˆ H, F, Cl, and OH) molecular systems with complete basis set and gaussian ab initio methods were used for accurate evaluations of their enthalpies of formation, bond dissociation energies, relative energies, and activation barriers of rotation and isomerization. It was demonstrated that experimentally determined enthalpies of formation for nitroge...

Pii: S0166-1280(98)00551-x

The Direct Reaction Field approach is briefly reviewed. Preliminary reports of the calculations on solvent induced shifts in the p* ← n transition of acetone in various solvents, and the dissociation of tert-butyl chloride in water are given. q 1999 Elsevier Science B.V. All rights reserved.

Pii: S0166-1280(99)00354-1

We have investigated linear, starbranched and hyperbranched XnHm polymers and determined the number of atoms, rotors, internal coordinates, valence and HOMO molecular orbitals as well as molecular mass for each generation and valency. We use the semi-empirical MNDO model to obtain full geometry optimization for increasingly larger clusters for each generation in order to obtain total relative e...