The thermochemical network of 300 isodesmic reactions was used to simultaneously adjust the enthalpies of formation for 25 adamantanes. The experimental enthalpies of formation of these compounds were treated as unknowns in the least-squares minimization of deviations between the theoretically predicted enthalpies of reaction and experimental values. The theoretical enthalpies of reactions were obtained using Gaussian-4 (G4) method. A result of a least-squares fit confirms the accuracy of experimental enthalpies of formation of 15 adamantanes, whereas the experimental measurements for 10 adamantanes require re-examination. (C) 2018 Elsevier Ltd.