Molecular properties, crystal structure, Hirshfeld surface analysis and computational calculations of a new third order NLO organic crystal, 2-aminopyridinium benzilate

摘要： A third order nonlinear optically active (NLO) organic proton transfer compound was synthesized by the reaction between 2-aminopyridine and benzilic acid. Single crystals of the product, 2-aminopyridinium benzilate, (2-APB) were grown by slow evaporation technique and the structure of 2-APB was confirmed by single crystal X-ray diffraction. In the structural network, cations and anions are linked through N+-H…O- intermolecular hydrogen bonding interactions. Elemental analysis, thermal analysis, UV-Vis, FT-IR and 1H and 13C NMR spectroscopic analyses were carried out to assess the structure and chemical makeup of the 2-APB crystal. Computational studies that include optimization of molecular geometry, natural bond orbital (NBO), Mulliken atomic charge and HOMO-LUMO analyses were also performed using B3LYP method at 6-311+ G (d,p) level of theory to explore various intermolecular interactions especially hydrogen bonding. Hirshfeld surface analysis indicates that the contacts involving hydrogen such as H…H, C…H and O…H have greater influence on the molecular properties of 2-APB.