Mon. Not. R. Astron. Soc., 465, 1137-1143 (2017/February-2)
Rotational excitation of 36ArH+ by He at low temperature.
BOP C.T., HAMMAMI K., NIANE A., FAYE N.A.B. and JAIDANE N.
Abstract (from CDS):
In this paper, we focus on the determination of the rotational excitation rate coefficients of the first observed molecule containing noble gas 36ArH+ isotope by He. Hence, we present the first potential energy surface (PES) of ArH+ -He van der Waals system. The interaction PES of the ArH+(X1Σ+)-He(1S) complex is calculated by the ab initio explicitly correlated coupled cluster with single, double, and perturbative triple excitation (CCSD(T)-F12) method in connection with the augmented correlation consistent triple zeta Gaussian basis (aug-cc-pVTZ). The interaction potential presents two global minima of 708.00 and 172.98 cm–1 below the ArH+(X1Σ+)-He(1S) dissociation limit. Using the PES obtained, we have computed integral inelastic cross-sections in the close-coupling approach among the first 11 rotational levels of ArH+ for energies up to 2500 cm–1. Downward rate coefficients were determined at low temperature (T <= 300 K). It is expected that the data worked out in this study may be beneficial for further astrophysical investigations as well as laboratory experiments.