Supramolecularassemblies through hydrogen bonding and Br…Onitro interactions in 4-bromoanilinium 2,4-dinitrobenzoate crystals

Abstract An organic crystal, 4-bromoanilinium 2,4-dinitrobenzoate (BDNB), was synthesized and crystallized by slow evaporation method. The formation of the compound was confirmed by analyzing vibrational frequencies of differentfunctional groups by FT-IR spectroscopy.Proton NMR and 13C NMR spectroscopic techniques were used to establish the positions and number of protonsas well as carbonsin the skeleton of BDNB. The compound is thermally stable up to 170 °C. The structure was confirmed by single crystal X-ray diffraction (XRD) analysis. XRD analysis reveals the network of intensive and excessive hydrogen bonding in BDNB. Br...Onitro and N-H...O interactions in BDNB extend throughout the molecule along ‘b’ axis via head-tail arrangement in the crystalstructure. Hirshfeld surface analysis was used to explore intermolecular interactions in BDNB. Intermolecular charge transfer in the molecule was confirmed by NBO analysis. Quantum chemical calculations reveal that the calculated first hyperpolarizability is 28 times higher than that of the reference material urea.