title: Molecular collisions and reactive scattering in external fields: Are field-induced couplings important at short range?
abstract: We use accurate quantum scattering calculations to elucidate the role of short-range molecule-field interactions in atom-molecule inelastic collisions and abstraction chemical reactions at low temperatures. We consider two examples: elastic and inelastic scattering of NH(Σ3) molecules with Mg(S1) atoms in a magnetic field; reactive scattering LiF + H → Li + HF in an electric field. Our calculations suggest that, for non-reactive collision systems and abstraction chemical reactions, the molecule-field interactions cannot generally be neglected at short range because the atom-molecule potential passes through zero at short range. An important exception occurs for Zeeman transitions in atom-molecule collisions at magnetic fields ≲1000 G, for which the molecule-field couplings need only be included at large ρ outside the range of the atom-molecule interaction. Our results highlight the importance of an accurate description of ρ-dependent molecule-field interactions in quantum scattering calculations on molecular collisions and chemical reactions at low temperatures.
authors.affiliation: Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Vieira
authors.affiliation: Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada.
authors.forename: R V
authors.initials: RV
authors.lastname: Krems
authors.affiliation: Department of Physics, University of Nevada, Reno, Nevada 89557, USA.
authors.forename: T V
authors.initials: TV
authors.lastname: Tscherbul