An Organized Collection of Theoretical Gas-Phase Geometric, Spectroscopic, and Thermochemical Data of Oxygenated Hydrocarbons, CxHyOz (x, y = 1, 2; z = 1–8), of Relevance to Atmospheric, Astrochemical, and Combustion Sciences

The objective of this work is to present a unified collection of structural and chemical information on a series of neutral chemical tri-elemental species up to a molecular formula C2H2O8, which may be used for validation purposes, for deep structured learning or indeed more simply for basic data of a single species. Such a collection vastly is tightly focused in terms of its component parts, contains novel results, and covers a number of chemical classes including stable molecules, radicals, carbenes, dipolar species, and excited states. Wherever possible, comparisons are made to the experimental and quantum chemical literature of gas-phase molecules, but the paucity of such means that there is only a very limited scope for validation. The primary data consist of structural information in the form of Cartesian coordinates, rotational constants together with vibrational frequencies, and anharmonicity coefficients, all obtained through density functional, B3LYP, calculations with the cc-pVTZ+d basis set. Standard statistical thermodynamic relations are then used to compute entropy, specific heat at constant pressure, and an enthalpy function over temperatures from 298.15 K to 2000 K. Supplementary material contains all the information necessary to carry out these calculations over different conditions as required as well as the raw species data. High-level quantum mechanical computations employing composite model chemistries, including CBS-QB3, CBS-APNO, G3, G4, W1BD, WMS, W2X, and W3X-L, are used to derive formation enthalpies via atomization and/or isodesmic calculations as appropriate.