Chemistry of hydrogen fluoride in the interstellar medium

A comprehensive account is given of the chemistry of HF in interstellar clouds. Calculations are presented of the rate coefficients for the quenching of F(P-2(1/2)) and for the reaction of F(P-2(3/2)) atoms in collisions with H-2. They confirm the conclusions of Neufeld and coworkers that gaseous fluorine exists in interstellar clouds almost entirely in the form of the molecule HF.