  Rate coefficients for inelastic Mg+H collisions are calculated for all
transitions between the lowest seven levels and the ionic state (charge
transfer). The rate coefficients are based on cross-sections from full quantum
scattering calculations, which are themselves based on detailed quantum
chemical calculations for the MgH molecule. The data are needed for non-LTE
applications in cool astrophysical environments, especially cool stellar
atmospheres, and are presented for a temperature range of 500-8000 K. From
consideration of the sensitivity of the cross-sections to various uncertainties
in the calculations, most importantly input quantum chemical data and the
numerical accuracy of the scattering calculations, a measure of the possible
uncertainties in the rate coefficients is estimated.
