Radiative charge transfer in cold and ultracold sulphur atoms colliding with protons. (14th April 2015)

• Record Type: Journal Article
• Authors: Shen, G; Stancil, P C; Wang, J G; McCann, J F; McLaughlin, B M
• Is Part Of: Journal of physics. Volume 48:Number 10(2015:May 15)
• Publication Date: 2015-04-14
• Subjects: ultracold collisions -- radiative loss -- rate coefficients; 31.15.A -- 31.15ae -- 34.50 Cx -- 34.70.+e; Atoms -- Periodicals; Molecules -- Periodicals; Optics -- Periodicals; Nuclear physics -- Periodicals; 539.6
• DOI: 10.1088/0953-4075/48/10/105203
• Languages: English
• ISSNs: 0953-4075

Abstract

Abstract: Radiative decay processes at cold and ultra cold temperatures for sulfur atoms colliding with protons are investigated. The MOLPRO quantum chemistry suite of codes was used to obtain accurate potential energies and transition dipole moments, as a function of internuclear distance, between low-lying states of the SH + molecular cation. A multi-reference configuration-interaction approximation together with the Davidson correction is used to determine the potential energy curves and transition dipole moments, between the states of interest, where the molecular orbitals are obtained from state-averaged multi-configuration-self-consistent field calculations. The collision problem is solved approximately using an optical potential method to obtain radiative loss, and a fully two-channel quantum approach for radiative charge transfer. Cross sections and rate coefficients are determined for the first time for temperatures ranging from 10 μ K up to 10 000 K. Results are obtained for all isotopes of sulfur, colliding with H + and D + ions and comparison is made to a number of other collision systems.