topological indices are the numerical value associated with chemical constitution purporting for correlation ofchemical structure with various physical properties, chemical reactivity or biological activity. graph theory is adelightful playground for the exploration of proof techniques in discrete mathematics and its results haveapplications in many areas of sciences. one of the useful indices ...

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...

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...

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...

Ab initio calculations at HF/6-31G* level of theory for geometry optimization and MP2/6-31G*//HF/6-31G*for total energy calculation are reported for Z-cyclooctene (1). The most favorable conformation of 1 is theunsymmetric boat-chair (1-BC) geometry. Potential energy profiles for two different boat-chair/boat-chairinterconversion processes were calculated. The process via a chair transition sta...

An empirical potential energy surface has been developed for the Ne·OH/D complexes from the experimentally observed vibrational and rotational energy levels with ab initio calculations being used for initial esti-

We present a global ground-state potential energy surface for N4 suitable for treating high-energy vibrational-rotational energy transfer and collision-induced dissociation in N2-N2 collisions. To obtain the surface, complete active space second-order perturbation theory calculations were performed for the ground singlet state with an active space of 12 electrons in 12 orbitals and the maug-cc-...

The determination of potential energy surfaces ~PES! from values calculated ab initio at a set of points or from spectral data ~vibration–rotation energy level information and rotation constants! are important and often difficult problems. The former is a ‘‘potential interpolation’’ problem, the latter a ‘‘potential inversion’’ problem. These are indeterminate problems in which the known data i...

We present high-level ab initio calculations for the global adiabatic potential energy surfaces of the ground state (X̃ A8) and several excited states ~Ã A8, B̃ A9, C̃ A8, D̃ A8, and Ẽ A9! of LiFH, including the valleys leading to Li1HF and LiF1H. The ab initio calculations were carried out using the multireference singles and doubles configuration interaction method with 99 reference configuration...