Implications of rotation–inversion–permutation invariance for analytic molecular potential energy surfaces

Implications of rotation–inversion–permutation invariance for analytic molecular potential energy surfaces

Advanced Potential Energy Surfaces for Molecular Simulation.

Advanced potential energy surfaces are defined as theoretical models that explicitly include many-body effects that transcend the standard fixed-charge, pairwise-additive paradigm typically used in molecular simulation. However, several factors relating to their software implementation have precluded their widespread use in condensed-phase simulations: the computational cost of the theoretical ...

Potential-energy surfaces and their dynamic implications

Accurate density functional and ab initio calculations have been performed to study the potential-energy surfaces (PESs) and their implications for kinetics and dynamics of : (1) the spin-forbidden reaction CH(2%) PES characteristics are calculated and used to ] 2 HCN] N(4S) ; evaluate the overall rate using non-adiabatic transition-state theory. (2) Gasphase ionÈmolecule reactions : PESs are c...

Molecular Potential Energy Surfaces by Interpolation

A moving interpolation technique which provides an accurate representation of potential energy surfaces for polyatomic molecules is presented. The method uses the ab initio energy, energy gradient, and second derivatives calculated at dynamically important configurations. The interpolant of the energy and its derivatives converges to the exact value with increasing number of data. A procedure i...

Molecular potential energy surfaces by interpolation: strategies for faster convergence.

A method for interpolating molecular potential energy surfaces introduced [Ischtwan and Collins, J. Chem. Phys. 100, 8080 (1994)] and developed as an iterative scheme has been improved by different criteria for the selection of the data points. Refinements in the selection procedure are based on the variance of the interpolation and the direct exploration of the interpolation error, and produce...