Ab initio potential energy surfaces for NH-NH with analytical long range
Abstract
We present four-dimensional ab initio potential energy surfaces for the three spin states of the NH-NH complex. The potentials are partially based on the work of Dhont et al. [J. Chem. Phys. 123, 184302 (2005)]. The surface for the quintet state is obtained at the RCCSD(T)/aug-cc-pVTZ level of theory and the energy diferences with the singlet and triplet states are calculated at the CASPTn/aug-cc-pVTZ (n = 2; 3) level of theory. The ab initio potentials are fitted to coupled spherical harmonics in the angular coordinates, and the long range is further expanded as a power series in 1/R. The RCCSD(T) potential is corrected for a size-consistency error prior to fitting. The long-range coeficients obtained from the fit are found to be in good agreement with perturbation theory calculations.
Keywords
Cite
@article{arxiv.0909.3417,
title = {Ab initio potential energy surfaces for NH-NH with analytical long range},
author = {Liesbeth M. C. Janssen and Gerrit C. Groenenboom and Ad van der Avoird and Piotr S. Żuchowski and Rafal Podeszwa},
journal= {arXiv preprint arXiv:0909.3417},
year = {2015}
}
Comments
submitted to JCP, supporting information available from authors on request