Crystal structure, physico-chemical characterization and Hirshfeld surface analysis of a new 0D pyridinium dichlorido(dihydrogenphosphato-O,O′)zinc(II)

Abstract

A new zero-dimensional (0D) chloro-substituted zincophosphate monomer, namely pyridinium dichlorido(dihydrogenphosphato-O,O′)[zinc (II), C5H5NH]ZnCl2(H2PO4), was synthesized via slow evaporation method at room temperature and structurally characterized by single-crystal X-ray diffraction. The structure of this compound is made up of an alternate ZnO2Cl2 and PO2(OH)2 tetrahedra, forming isolated four-membered rings [(ZnCl2PO2(OH)2)2]2− units accompanied by pyridinium cation. The crystal packing is consolidated by O–H···O, O–H···Cl, N–H···Cl and C–H···O hydrogen bonding system and offset π–π interactions, involving anti-parallel neighboring pyridinium rings (inter-centroid distance 3.65 A), which is supported by Columbic attractions between C5H5NH+ cations and (ZnCl2PO2(OH)2)− anions, and Van Der Waals interactions, forming also a supramolecular 3D structure. We discuss quantitatively these interactions using the Hirshfeld surfaces associated with 2D fingerprint plots. This compound was further characterized by solid-state NMR, infrared spectroscopies and DTA/TGA analysis. Solid-state 31P and 13C MAS-NMR spectroscopy results are in full agreement with the X-ray structure.