The metadata for the sample in the Chemotion repository are described as comprehensively as possible, including the description of the components characterizing the samples, their properties, and additional references to analytical data and the synthetic origin of the sample (chemical reaction). In particular, the reference to the analytical data and the reactions allows the re-use of the data, as this information is needed for chemists to reproduce the experiments. A plurality of additional data describing the sample further can be gained from the latter two references.