The full identification of a substance under REACH requires the following information:
Chemical composition of the substance, considering, where appropriate, impurities and additives besides main constituent(s) and respective typical concentrations and concentration ranges;
Chemical identity of the constituent(s) by means of IUPAC name plus other identifiers when available, e.g. EC number, CAS number. For UVCB substances information on the source and manufacturing process is also necessary;
Molecular and structural information; this must be defined, when available and appropriate, by molecular and structural formula, information on optical activity, ratio of isomers, molecular weight or molecular weight range;
Spectral and analytical data sufficient to confirm the structure and the composition of the substance.
The data to enable a substance to be identified are listed in section 2 of REACH Annex VI. As a general rule, all this information is required regardless of the substance type. However, if it is not technically possible or not scientifically necessary to give a particular piece of information, a reasoned justification should be stated to enable the scientific validity to be assessed.