X-ray structure of 4-aminopyridinium-oxalate-oxalic acid-hydrate (1/1/0.5/0.5) and its characterization

Abstract

Single crystal of 4-Aminopyridinium-oxalate-oxalicacid-hydrate (1/1/0.5/0.5) (C5H7N2+. C2HO4-. 0.5 C2H2O4. 0.5 H2O) (4APOOAH) was synthesized and grown by slow evaporation solution growth technique. The grown was subjected to three dimensional X-ray crystallography which reveals that the crystal 4APOOAH crystallized in the triclinic crystal system (CCDC No.: 1949668) with the cell parameters (a = 3.7110(6) Å, b = 9.5021(18) Å, c = 15.294(2) Å, α = 73.215(7)⁰, β = 84.243(7)⁰, γ = 81.025(8)⁰ and V = 509.13(14) Å3). The carboxyl O atom of the oxalate anion link the 4-Aminopyridinium cation, semioxalic acid and semi hydrate molecule. The crystal packing stabilized by Ohydroxyl—H⋯Ocarboxyl, Namino—H⋯Ocarboxyl hydrogen bonding and further stabilized by very weak C–H…O hydrogen bonding. The hydrogen bonding in disordered position I and II of hydrogen atom of title compound analysed from Hirshfeld surface analysis. In the title compound, hydrogen oxalate and hydrate molecule disordered over two positions of equal occupancy. The hydrogen bonding in disordered position I and II of hydrogen atom of title compound analysed from Hirshfeld surface analysis. The functional groups identified from Fourier Transform Infrared (FT-IR) spectrum. The absorption property of the 4APOOAH material was measured using UV–vis-NIR spectral analysis and the cut off wavelength is found to be 277 nm. The energy band gap calculated from the tauc plot indicated that this material may considered as optical semiconducting materials.