Harmonic infrared and Raman spectra of fused polycyclic aromatic hydrocarbon isomers with one to ten rings

This dataset contains curated quantum-chemical infrared and Raman spectral records for neutral Kekulean benzenoid polycyclic aromatic hydrocarbon isomers composed of fused six-membered rings. The data were generated for two internally consistent calculation tiers. The def2-SVP tier contains 18,360 PAH structures with one to ten fused rings. The def2-TZVP tier contains 4,253 PAH structures with one to nine fused rings. Counting each molecule–basis-set calculation as one spectral entry, the complete release contains 22,613 spectral records. All calculations were performed at the B3LYP-D3(BJ) level with Gaussian 16. The deposited spectra are unscaled harmonic stick spectra. Each per-molecule vibrational file reports harmonic frequencies, infrared intensities, Raman scattering activities, depolarization ratios, reduced masses, and force constants where available. The spectra are provided as stick lists rather than broadened curves so that users can apply their own scaling factors, line shapes, and instrumental broadening parameters. The dataset also includes optimized Cartesian geometries, thermochemical quantities at 298.15 K, frontier orbital energies, rotational constants, dipole moments, isotropic polarizabilities, point groups, molecular formulae, and structural identifiers where available. Summary tables are provided in CSV, Parquet, and HDF5 formats for compatibility with different analysis workflows. The main archive contents are organized as follows: - dataset/ Curated data tables and metadata for the complete release. - metadata_combined.json, metadata_SVP.json, metadata_TZVP.json - summary_table_combined.csv, summary_table_combined.parquet, summary_table_combined.h5 - summary_table_SVP.csv, summary_table_SVP.parquet, summary_table_SVP.h5 - summary_table_TZVP.csv, summary_table_TZVP.parquet, summary_table_TZVP.h5 - dataset/SVP/ B3LYP-D3(BJ)/def2-SVP data. - README.md and metadata.json - summary_table_SVP.csv, summary_table_SVP.parquet, summary_table_SVP.h5 - structures/*.xyz: optimized Cartesian geometries - vibrations/*_freq.csv: per-molecule harmonic IR/Raman stick spectra - dataset/TZVP/ B3LYP-D3(BJ)/def2-TZVP data. - README.md and metadata.json - summary_table_TZVP.csv, summary_table_TZVP.parquet, summary_table_TZVP.h5 - structures/*.xyz: optimized Cartesian geometries - vibrations/*_freq.csv: per-molecule harmonic IR/Raman stick spectra - analysis/ Basis-set comparison outputs, including mode-pair matching results and summary statistics for the molecules common to the SVP and TZVP tiers. - figures/ Figure source files, validation tables, and generated graphical outputs used to document and check the dataset. - validation/measured_raman/ Measured Raman spectra used for experimental comparison. - validation/nist_ir/ NIST gas-phase infrared reference spectra used for external validation. - MANIFEST_SHA256.csv SHA256 checksums and file sizes for the deposited files. - PATH_AUDIT.csv Mapping between the local source paths used during packaging and the paths staged in this Zenodo archive. - PACKAGE_SUMMARY.json Machine-readable package-level metadata. The molecule identifier follows the format PAH_R<NN>_<NNNNNN>, where <NN> is the zero-padded number of fused rings and <NNNNNN> is the zero-padded enumeration index within that ring count. The same identifier is used consistently across summary tables, XYZ geometry files, and per-molecule vibrational CSV files. Imaginary-frequency information is included in the summary tables and metadata. Raw negative-frequency counts are reported as n_imaginary. Frequencies between 0 and -50 cm^-1 are treated as soft numerical or quasi-free modes and reported as n_soft_imaginary. Frequencies at or below -50 cm^-1 are treated as effective imaginary modes and reported as n_imaginary_effective. Under this threshold convention, no record in this release has an effective imaginary frequency. The dataset is intended for reuse in molecular spectroscopy, PAH spectral-library construction, astrochemistry, combustion chemistry, molecular informatics, and benchmarking of calculated vibrational spectra. The raw Gaussian output files are not included; this record provides curated geometries, tabulated molecular properties, and parsed vibrational data suitable for downstream analysis. License: Creative Commons Attribution 4.0 International, CC BY 4.0.