A new ground electronic state potential energy surface of HeLiH+: Analytical representation and investigation of the dynamics of He + LiH+ (v = 0, j = 0) → LiHe+ + H reaction

An improved global potential energy surface (PES) for the electronic ground state of the HeLiH+ system is reported. The data points are calculated at the full configuration-interaction level of theory and extrapolated to the complete basis set limit. The fitting procedure implements a combination of neural network and Aguado–Paniagua functional forms to fit the ab initio data points. The fitted surface reproduces the ab initio data points accurately in short as well as long ranges and has an overall root mean square error of 1.76 × 10−3 eV (14.21 cm−1) in energy space