Аннотация:Two crystalline compounds - (NH4)HProp2 and (NH4)Prop (HProp = C2H5COOH) are obtained by the interaction of ammonia with propionic acid. Their crystal structures are determined by X-ray diffraction. Both compounds crystallize in the monoclinic crystal system (space groups C2/c and P21/n respectively) and consist of alternating NH4+ and Prop– ions (or hydrogen-bonded pairs Prop–H⋯Prop–) organized into a 3D framework via hydrogen bonds. The structural feature of the (NH4)HProp2 compound, namely, the positional disorder of acidic hydrogen atoms between carboxyl groups of propionate anions, is studied by maximum entropy and DFT methods. Similar to homologous ammonium carboxylates, (NH4)Prop is extremely unstable under atmospheric conditions whereas (NH4)HProp2 acidic salt is stable during storage and can be used for the further synthesis of metal propionates.
