Ab initio potential energy surfaces of Ar–H2O and Ar–D2O

Ab initio computed diabatic potential energy surfaces of OH-HCl.

The two four-dimensional diabatic potential energy surfaces (DPESs) for OH-HCl are computed that correlate with the twofold degenerate (2)Pi ground state of the free OH radical. About 20 000 points on the surface are obtained by the ab initio coupled-cluster and multi-reference configuration interaction methods. Analytic forms for the diabatic potential energy surfaces are derived as expansions...

Quantum and Classical Vibrational Relaxation Dynamics of N -Methylacetamide on Ab Initio Potential Energy Surfaces

Employing extensive quantum-chemical calculations at the DFT/B3LYP and MP2 level, quartic force fields of isolated N-methylacetamide are constructed. Taking into account 24 vibrational degrees of freedom, the model is employed to perform numerically exact vibrational configuration interaction calculations of the vibrational energy relaxation of the amide I mode. It is found that the energy tran...

The interaction of OH(X²Π) with H₂: ab initio potential energy surfaces and bound states.

For the interaction of OH(X(2)Π) with H2, under the assumption of fixed OH and H2 bond distances, we have determined two new sets of four-dimensional ab initio potential energy surfaces (PES's). The first set of PES's was computed with the multi-reference configuration interaction method [MRCISD+Q(Davidson)], and the second set with an explicitly correlated coupled cluster method [RCCSD(T)-F12a...

Ab initio potential energy surfaces, bound states, and electronic spectrum of the Ar-SH complex.

New ab initio potential energy surfaces for the (2)Pi ground electronic state of the Ar-SH complex are presented, calculated at the RCCSD(T)/aug-cc-pV5Z level. Weakly bound rotation-vibration levels are calculated using coupled-channel methods that properly account for the coupling between the two electronic states. The resulting wave functions are analyzed and a new adiabatic approximation inc...

Representation of ab initio energy surfaces by analytic functions