Synthesis, crystal structure determination, DFT calculation, and Hirshfeld surface analysis of a new Zn(II) complex with the guaninium ligand

Abstract

A new Zn(II) complex with the guaninium monodentate ligand, [ZnCl3(C5H6N5O)], has been synthesized in aqueous solution and studied by single-crystal X-ray diffraction, elemental analysis, CP-MAS-NMR, and IR spectroscopy. The Zn(II) atom is coordinated in a distorted tetrahedral fashion by three chloride anions and one nitrogen atom of the guaninium cation. The compound crystallizes in the monoclinic space group P21/n with lattice parameters a = 8.8411(7) Å, b = 11.7176(5) Å, c = 10.3765(8) Å, β = 100.069(4)°, V = 1058.41(13) Å3, and Z = 4. Intermolecular interactions were investigated by Hirshfeld surfaces. Besides the Zn(II) cation coordination, the crystal packing is stabilized by intermolecular N-H…O, N-H…Cl− and C-H…Cl− hydrogen bonds and C…C aromatic stacking which link the molecules into a three-dimensional network. The regions of strongest positive electrostatic on the Hirshfeld surface of guaninium ligand interact with electronegative atoms and vice versa. The 13C and 15N CP-MAS NMR spectra are discussed and the vibrational absorption bands were identified by infrared spectroscopy. The HOMO and LUMO energies and Molecular Electrostatic Potential surface were derived from DFT theoretical calculations.