An update of and suggested increase in calculated radiative association rate coefficients

Abstract

A sizable number of radiative association reaction rate coefficients involving polyatomic molecular ions have now been calculated and utilized in ion-molecule models of the chemistry of dense interstellar clouds. Recent evidence suggests that these calculated rate coefficients may be an order of magnitude too low in many cases. The evidence is reviewed and developed and calculated rate coefficients are updated. In addition, the temperature dependence of each reaction rate coefficient in the 10--50 K range is estimated if this information has not previously appeared in the literature.