In the above paper, I have debated the reliability of the existing literature data on the standard (partial at infinite dilution) molar volumes and expansibilities of hexamethylenetetramine (HMT) in heavy water (D2O) and the corresponding D2O‒H2O solvent isotope effects. Based mainly on the results of two works under comparison [C.M. Romero and H.J. Mesa, J. Mol. Liq. 242 (2017) 244-248; Yu.P. Pankratov and V.K. Abrosimov, Russ. J. Phys. Chem. 71 (1997) 1263-1266], a general conclusion about the pronounced inconsistencies in the discussed quantities for the solute in both in (H2O + HMT) and (D2O + HMT) has been made. This fact initiated a necessity carrying out the additional high-precision densimetric study of these binary liquid systems, followed by estimating the volume-isotope characteristics of interest. Such a study has been done and its results are reported in the present work. Primarily, it is confirmed here the conclusion on the doubtfulness of results derived by both authors’ groups being analyzed in comparison.
