While the NIST dataset could be ordered and was used as is, our open-access database for easily accessible IR data needed to be prepared. As a source, we used the repository Chemotion , which is a publicly funded research data repository hosted at the Karlsruhe Institute of Technology (KIT) in Germany. The Chemotion repository comprises experimental data obtained from the characterization of chemical compounds, such as 1H NMR data, 13 C NMR data, IR data, mass spectrometry data, and several other techniques. The analyzed compounds were synthesized across various chemical laboratories, primarily aiming to validate findings in scientific publications. To obtain IR spectra and the related molecular structures from the Chemotion repository, we exported parts of the database content. The obtained files were further processed as described in the methods section. An alternative way to obtain data from the Chemotion repository is to fetch the whole dataset available in Chemotion via the API and to reduce the dataset to the required spectra types and related information. In the exported dataset from the Chemotion repository, there were 4175 samples with assigned IR spectra. Most of the data came from the chemical labs at the Karlsruhe Institute of Technology, with a smaller portion contributed by other research institutes. Each sample includes an IR spectrum, molecular SMILES code, and corresponding functional group labels after data preprocessing. Following our data preprocessing pipeline (mentioned in the section below) we end up with a dataset with 1763 samples. We call this preprocessed version of the dataset "Chemotion". Chemotion holds the distinct advantage of being open-source, and readily accessible for utilization. To facilitate easy and inexpensive research in field of machine learning for IR spectrum analysis, we published the IR dataset Chemotion in an open-access repository.