A new ab initio potential-energy surface for NH2(X 2A") and quantum studies of NH2 vibrational spectrum and rate constant for the N(2D)+H2-->NH+H reaction

Shulan Zhou; Daiqian Xie; Shi Ying Lin; Hua Guo

doi:10.1063/1.2939016

A new ab initio potential-energy surface for NH2(X 2A") and quantum studies of NH2 vibrational spectrum and rate constant for the N(2D)+H2-->NH+H reaction

J Chem Phys. 2008 Jun 14;128(22):224316. doi: 10.1063/1.2939016.

Authors

Shulan Zhou¹, Daiqian Xie, Shi Ying Lin, Hua Guo

Affiliation

¹ Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.

PMID: 18554022
DOI: 10.1063/1.2939016

Abstract

A new global potential-energy surface for the ground electronic state of NH(2)(X (2)A(")) has been constructed by three-dimensional cubic spline interpolation of more than 20 000 ab initio points, which were calculated at the multireference configuration-interaction level with Davidson correction using the augmented correlation-consistent polarized valence quadruple-zeta basis set. The new potential is shown to yield better overall agreement with the experimental vibrational frequencies of NH(2) and its isotopomers. In addition, the rate constant for the N((2)D)+H(2)(X (1)Sigma(g) (+))-->NH(X (3)Sigma(-))+H((2)S) reaction was calculated up to 600 K and the agreement with experimental data is substantially improved over previous results.