[@15TaCa].

The original ExoMol data structure was very focused in its goal, with the scope of the data limited to generating lists of transitions [@jt548]. However, it has become obvious that the potential applications of the ExoMol spectroscopic data are much more diverse. For example, the ExoMol data can be used to compute partition functions [@jt571], cross sections [@jt542], lifetimes [@jt624], Landé $g$-factors [@jtgfac] and other properties. Our aim is to systematically provide this additional data to maximise its usefulness. To do this requires significant extension of the ExoMol data structure, which is the major purpose of this paper. At the same time this implementation should facilitate the adoption of an application programming interface (API) between the database and programs using it. Similar enhancements are actively being pursued by other related databases such as HITRAN [@jt559; @HAPI; @Honline]. A major new feature is the inclusion, albeit at a fairly crude level, of pressure-broadening parameters. These have been shown to be important for models of exoplanets [@jt521; @16HeMaxx] and are known to be vital for many other applications. Section 2 summarizes current data coverage of the ExoMol database. Section 3 reviews the individual line lists included in the database with particular 