Structural Investigation, Quantum Mechanical Study and Hirshfeld Surface Analysis of One Novel Adduct Based on Aminopyridinium and Biphenyl-2,4'-dicarboxylate

One novel adduct based on aminopyridinium and biphenyl-2,4′-dicarboxylate, C5H7N2+·C14H9O4-, has been synthesized and characterized by X-ray structural study. The compound crystallizes in trigonal, space group P32 with a = 9.2886(16), b = 9.2886(16), c = 16.746(6) , γ = 120°, V = 1251.2(5) 3, C19H16N2O4, Mr = 336.34, Dc = 1.339 g/cm3, μ(MoKα) = 0.095 mm-1, F(000) = 528, Z = 3, the final R = 0.0438 and wR = 0.1119 for 3097 observed reflections (Ⅰ > 2σ(Ⅰ)). Its electronic structure was calculated at the RHF/6-31G(d) level and a detailed analysis of intermolecular interactions was used by Hirshfeld surface and fingerprint plot. Intermolecular N–H…O hydrogen bonds link two components generating R22(8) rings which are linked into three one-dimensional chains in the [100], [010] and [110] directions, and these chains are finally arranged into a three-dimensional framework by hydrogen bonds. Investigation of intermolecular interactions via Hirshfeld surface analysis reveals that the close contacts are mainly associated with the classical hydrogen bonding interactions. The HOMO-LUMO energy gap of the compound indicates a higher kinetic stability.