For HTBZ-HOX, an additional mass loss of approximately 3.53 % was observed at 110 °C. To gain insights into the nature of this mass loss, we conducted PXRD analysis before and after heating the sample to 210 °C (after DSC measurement). Interestingly, the PXRD patterns did not reveal any changes in the crystal structure of the sample, indicating that it remained identical to the HTBZ-HOX structure determined by SC-XRD. Our hypothesis is that this thermal event corresponds to the sample's water content loss. The presence of water molecules in HTBZ-HOX can be attributed to either physio-sorption on the surface of the anhydrous HTBZ-HOX or the existence of an amorphous oxalic acid hydrate. The mechanochemical synthesis can sometimes also lead to amorphous intermediates . The relatively high temperature required for water loss suggests the presence of the latter. Oxalic acid is known to be a hygroscopic solid . That is why the dihydrate form was utilized as a reactant to prepare HTBZ-HOX. The asprepared salt was heated (3 hours at 120 °C) and cooled to obtain the anhydrous sample, HTBZ-HOX (dry).