Regular Article

Structure, spectroscopy and cold collisions of the (SrNa)⁺ ionic system

¹ Laboratory of Interfaces and Advanced Materials, Physics Department, Faculty of Science, University of Monastir, 5019 Monastir, Tunisia
² Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
³ Sidhu Kanhu Birsa Polytechnic, Keshiary, Paschim Medinipur 721133, India
⁴ Raman Center for Atomic, Molecular and Optical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
⁵ Mathematics and Natural Sciences Department, School of Arts and Sciences, American University of Ras Al Khaimah, Ras Al Khaimah PO Box 10021, RAK, United Arab Emirates

^a e-mail: hamid.berriche@aurak.ac.ae

Received: 7 February 2018
Received in final form: 3 April 2018
Published online: 2 August 2018

Abstract

We perform a study on extended adiabatic potential energy curves of nearly 38 states of ^1,3Σ⁺, ^1,3Π and ^1,3Δ symmetries for the (SrNa)⁺ ion, though only the ground and first two excited states are used for the study of scattering processes. Full interaction configuration (CI) calculations are carried out for this molecule using the pseudopotential approach. In this context, it is considered that two active electrons interact with the ionic cores and all single and double excitations were included in the CI calculations. A correction including the core-core electron interactions is also considered. Using the accurate potential energy data, the ground state scattering wave functions and cross sections are obtained for a wide range of energies. We find that, in order to get convergent results for the total scattering cross sections for energies of the order 1 K, one need to take into account at least 87 partial waves. In the low energy limit ( <1 mK), elastic scattering cross sections exhibit Wigner law threshold law behavior while in the high energy limit the cross sections go as E^−1∕3. A qualitative discussion about the possibility of forming the cold molecular ion by photoassociative spectroscopy is presented.