The thermochemical properties of 2- and 3-Thiophenemethanol: Eluding incomplete combustion issues through combining experimental and computational methodologies

Determining thermochemical properties of sulfur compounds is often precluded because they cannot be completely burnt in combustion calorimetry experiments, even when using roating-bomb calorimeters. In this work, we estimated the thermochemical properties of 2-thiophenemethanol ( ) and 3-thiophenemethanol ( ) through experimental and theoretical methodologies. We measured vaporization enthalpies using thermogravimetry and their liquid-phase heat capacities using differential scanning calorimetry. On the other hand, using a combination of four composite methods (G3, G3MP2, G4, and CBS-QB3) and Boltzmann-weighted averages, we calculated the thermochemical properties of the thiophenemethanols and the thiophene in the gas phase. The gas-phase thermochemical properties of thiophene were used to validate our theoretical methodology; we found that the differences between our theoretical estimations and previously reported experimental data are within the experimental uncertainties. The so-obtained thiophenemethanols’ vaporization and gas-phase formation enthalpies, together with their gas- and liquid-phase heat capacities, allowed to obtain the liquid-phase formation enthalpies of 2- and 3-thiophenemetanol for the first time. • Liquid-phase formation enthalpies of 2- and 3-thiophenemethanol are first-time reported. • Vaporization and gas-phase formation enthalpies and heat capacities are reported. • Experimental and theoretical methodologies are combined to elude incomplete combustion issues. • A theoretical recipe combining Boltzmann weighted averages and methods is proposed. • Gas-phase heat capacities are estimated at different temperatures.