With Python binding (which is normally provided), a default catalog can be created (in the local directory) by executing once @ gag_data:imager-linedb.sic This may take a while, and even get stuck occasionally because it performs network access to remote databases. You can later copy this catalog to your $HOME. See HELP LINEDB\ to add or remove species from such catalogs. Without Python binding, IMAGER provides a default Astro catalog in gag_data:molecules.dat.