Ideal-gas Thermochemical Properties for Carbon Dioxide and its Isotopologues Calculated from Partition Functions

Tabulations at 1 K intervals from 1 K to 6000 K of the partition function and standard-state isobaric heat capacity, entropy, and enthalpy for the 12 natural isotopologues of CO2, along with their standard uncertainties. Calculations performed with a partition function constructed from spectroscopic and theoretical data as described in the paper: S.A. Tashkun and A.H. Harvey, "Partition Functions and Ideal-Gas Thermodynamics for Carbon Dioxide," submitted to J. Phys. Chem. Ref. Data (2025). Note that the model does not account for dissociation of the CO2 molecule, making the results incomplete above approximately 3500 K. Text files have numbers for the corresponding isotopologue, where 6, 7, and 8 stand for the oxygen isotopes 16-O, 17-O, and 18-O, and where 2 and 3 stand for the carbon isotopes 12-C and 13-C. Thus, 626 refers to the most abundant isotopologue with two 16-O atoms and one 12-C atom. The file CO2-total.txt has values of the isobaric heat capacity, entropy, and enthalpy, and their standard uncertainties, calculated by averaging the 12 isotopologues according to the natural isotopic abundances as given by IUPAC. These heat capacities were used for the CO2 equation of state presented in the abovementioned paper.