Ab initio potential energy surface and quantum scattering studies of $$\hbox {Li}^{+}$$ Li + with $$\hbox {N}_{2}$$ N 2 : comparison with experiments at $$E_{\mathrm{c.m.}}= 2.47\,\hbox {eV}$$ E c . m . = 2.47 eV and 3.64 eV

Abstract

A new ground electronic state potential energy surface of $$\hbox {Li}^{+}+\hbox {N}_{2}$$ system is presented in the Jacobi scattering coordinates at MRCI level of accuracy employing the augmented correlation-consistent polarized valence quadrupole zeta (aug-cc-pVQZ) basis set. An analytic fit of the computed ab initio surface has also been obtained. The surface has a global minimum for the collinear geometry at the internuclear distance of $$\hbox {N}_{2}, r = 2.078a_{0}$$ , and the distance between $$\hbox {Li}^{+}$$ and $$\hbox {N}_{{2}}$$ , $$R = 4.96a_{0}$$ . Quantum dynamics studies have been performed within the vibrational close coupling-rotational infinite-order sudden approximation at $$E_{\mathrm{c.m.}} = 3.64$$ eV, and the collision attributes have been analyzed. The computed total differential cross-sections are found in quantitative agreement with those available from the experiments at $$E_{\mathrm{c.m.}}= 3.64\,\hbox {eV}$$ . The other dynamic attributes such as angle dependent opacities and integral cross-sections are also reported. Preliminary rigid-rotor and vibrational–rotational coupled-state calculations at $$E_{\mathrm{c.m.}} = 2.47\,\hbox {eV}$$ also support the experimental observation that the system exhibits a large number of rotational excitations in the vibrational manifold $$v = 0$$ . SYNOPSIS Quantum scattering dynamics studies for vibrational-rotational excitations of N2 upon collisions of Li+ have been carried out on a newly computed ground electronic state potential energy surface and the computed collision attributes are compared with those available from the experiments at collision energies, $$E_{\mathrm{c.m.}} = 2.47$$ eV and 3.64 eV