Hyperfine excitation of SH+ in collisions with para- and ortho-H2

Abstract

ABSTRACT Time-independent close-coupling quantum scattering calculations are employed to compute hyperfine-resolved rate coefficients for (de-)excitation of SH+ in collisions with para- and ortho-H2. These calculations utilized a potential energy surface for the interaction of SH+(X3Σ−) with H2 recently computed by the explicitly correlated RCCSD(T)-F12a coupled-cluster method. Rate coefficients for temperatures ranging from 10 to 500 K were calculated for all transitions among the first 37 hyperfine energy levels of SH+, with rotational angular momenta n ≤ 6, in collisions with para- and ortho-H2. As a first application of these data, the rate coefficients were employed in simple radiative transfer calculations to simulate the excitation of SH+ in typical molecular clouds.