A full dimensional potential for H2O2 (X(1)A) covering all dissociation channels

作者:Coelho Daniela V; Brandao Joao*
来源:Physical Chemistry Chemical Physics, 2017, 19(2): 1378-1388.
DOI:10.1039/c6cp05733k

摘要

This work presents a new full dimensional potential energy surface for the ground singlet state of hydrogen peroxide, H2O2. This potential is based on a 3 x 3 matrix to accurately reproduce all the different dissociation channels in accordance with the Wigner-Witmer rules, namely, O(D-1) + H2O(X(1)A(1)), OH(X-2 Pi) + OH(X-2 Pi), O-2(a(1)Delta(g)) + H-2(X-1 Sigma(+)(g)) e H(S-2) + HO2(X(2)A ''). It has been obtained by fitting more than 38 thousand ab initio energies computed using the aug-cc-pVTZ and aug-cc-pVQZ basis sets and extrapolated to the basis set limit. The functional form used to represent the four-body short-range interactions is based on a sum of polynomial functions of the fourth degree multiplied by a range factor, both built with intrinsic permutation symmetry and centred at specific reference geometries, to which the ab initio points computed are assigned based on a k-means algorithm. It also accounts for the electrostatic dipole-dipole interaction between two OH((2)Pi) fragments.

  • 出版日期2017