Regular Article

Non-adiabatic coupling as a frictional force in the formation of H₃⁺: a model dynamical study

¹ School of Chemical Sciences, Indian Association for the Cultivation of Science, Kolkata, India
² Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, India
³ The Fritz Haber Center for Molecular Dynamics, The Hebrew University of Jerusalem, Jerusalem, Israel

^a e-mail: nsath@iitk.ac.in

Received: 13 March 2020
Received in final form: 13 June 2020
Accepted: 6 October 2020
Published online: 8 December 2020

Abstract

By treating the non-adiabatic coupling terms (NACTs) in a molecular system as equivalent to a frictional force, the classical equation of motion is solved for a test case of quasi-H₃⁺ along the C_2v axis and axes parallel to it, and it is shown that the singular NACTs between the first two excited electronic states slow down the relative motion of the three quasi-ions (H,H,H)⁺ while approaching each other.