Line FWHM of all molecules detected in each tracer. Different colours indicate different species as in Fig. 9: carbon chains and hydrocarbons are characterised by blue-cyan-green colours and for each source they are plotted to the left on the x-axis; molecules with the cyanide group are indicated by red-orange-pink colours and are plotted to the right. The black stars are the FWHM derived from ammonia (2,2) (Fontani et al. 2015a). For each group, the molecules on the x-axis are ordered from left to right according to increasing number of atoms.