Dataset for the article "Anharmonic Infrared Spectra of Thermally Excited Pyrene (C16H10): A Combined View of DFT-Based GVPT2 with AnharmonicCaOs, and Approximate DFT Molecular dynamics with DemonNano" (DOI: 10.1016/j.jms.2021.111466) data_AC folder: data obtained with the AnharmoniCaOs package using a DFT-based quartic force field data_DFTB folder: data obtained with Molecular Dynamics running on a DFTB-based force field (provided by the DemonNano package) within each folder, the bp_T subfolder contains tabulated band positions as a function of temperature, whereas bw_T subfolder contains tabulated band widths as a function of temperature; the spectra subfolders contain actual raw computed anharmonic IR absorption spectra at various temperatures.