Chapter 5: Databases and Computer Software for Astrochemistry in Interstellar Clouds

Astrochemical models are used to compute the abundances of hundreds of interstellar molecular species, but these models require networks of very large numbers of chemical reactions to be specified. The huge amounts of data required to describe all of these reactions need to be organised and managed: so we need databases that enable these data to be used efficiently in the computations of molecular abundances. This chapter discusses the data needed in chemical kinetics and how these data are parametrised. Several databases in wide use are described, and three applications of these methods are explored, including the gas phase chemistry occurring in the early Universe, and in diffuse and translucent interstellar clouds of the Milky Way.