Amani Direm2024-02-142024-02-142010-06-102052-5206http://dspace.univ-khenchela.dz:4000/handle/123456789/997Three new proton transfer compounds, [2-ammonio-5-methylcarboxybenzene perchlorate (1), (C8H10NO2+ClO4 ), 4-(ammoniomethyl)carboxybenzene nitrate (2), (C8H10NO2+NO3 ), and 4-(ammoniomethyl)carboxybenzene perchlorate (3), (C8H10NO2+ClO4 )], have been synthesized, their IR modes of vibrations have been assigned and their crystal structures studied by means of singlecrystal X-ray diffraction. Their asymmetric units consist of one cation and one anion for both compounds (1) and (2). However, the crystal structure of compound (3) is based on a pair of cations and a pair of anions in its asymmetric unit. The three-dimensional Hirshfeld surface analysis and the two-dimensional fingerprint maps revealed that the three structures are dominated by H O/ O H and H H contacts. The strongest hydrogen-bonding interactions are associated with O—H O and N—H O constituting the highest fraction of approximately 50%, followed by those of the H H type contributing 20%. Other close contacts are also present, including weak C H/H C contacts (with about 10%)enArticle