A highly accurate ab initio potential energy surface for methane

Ab initio potential energy surface and second virial coefficient for Asp-His-Ser trimer

HF level of ab initio calculations with basis-set 6-31G including full counterpoise correction hasbeen applied to compute the AspHis potential with the Ser and HisSer potential with the Asp inAspHisSer trimer. The potential energy surface has a minimum of -16.765 kcal/mol in R1=1.912nm and R2=2.719 nm. The optimum computed curves for two interactions were fitted withintermolecular pair potentia...

An ab initio Potential Energy Surface for the Ne-CO

An ab initio potential energy surface for Ne–CO

A new ab initio two-dimensional potential energy surface for the Ne–CO interaction is described. The surface was obtained by the supermolecule method at the CCSD~T! level of theory. It is compared with several experimental data sets and with the symmetry-adapted perturbation theory ~SAPT! surface of Moszynski et al. @J. Phys. Chem. A 101, 4690 ~1997!#. The new surface gives modestly better pred...

An accurate ab initio HOCl potential energy surface, vibrational and rotational calculations, and comparison with experiment

Accurate ab initio multireference configuration interaction ~CI! calculations with large correlation-consistent basis sets are performed for HOCl. After extrapolation to the complete basis set limit, the ab initio data are precisely fit to give a semiglobal three-dimensional potential energy surface to describe HOCl→Cl1OH from high overtone excitation of the OH-stretch. The average absolute dev...

Analysis of the HO2 vibrational spectrum on an accurate ab initio potential energy surface.

The complete vibrational spectrum of the HO2(X(2)A' ') radical, up to the H + O2 dissociation limit, has been determined quantum mechanically on an accurate potential energy surface (PES), based on approximately 15000 ab initio points at the icMRCI+Q/aug-cc-pVQZ level of theory. The vibrational states are found to be assignable at low energies but become more irregular as the energy approaches ...