Crystal structure, Hirshfeld surface analysis and theoretical calculations of an oxalato-bridged copper(II) complex: mu-oxalato-bis[(2,2'-bipyridine) hydrate copper(II) nitrate]

Boutobba Z., Direm A., SAYIN K. , El Bali B., Lachkar M., Benali-Cherif N.

JOURNAL OF THE IRANIAN CHEMICAL SOCIETY, cilt.17, ss.671-685, 2020 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 17 Konu: 3
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1007/s13738-019-01805-0
  • Sayfa Sayıları: ss.671-685


The copper complex [Cu-2(Bipy)(2)(H2O)(2)(C2O4)(NO3)(2)] (Bipy=2,2 '-bipyridine; C2O42-=oxalate) has been synthesized and characterized by single-crystal X-ray diffraction and FTIR spectroscopy. The structure determination revealed that the title compound contains centrosymmetric doubly charged dinuclear oxalato-bridged copper(II) complex cations, nitrate counter ions and water molecules. In this complex, the oxalate ligand is coordinated in a bis-bidentate bridging mode to the copper atoms. Each Cu(II) atom has a distorted tetragonal-bipyramidal environment, being coordinated by two N atoms of a chelating 2,2 '-bipyridine ligand and two O atoms of the doubly deprotonated oxalate anion. Pairs of monodentate nitrate anions and aqua ligands are linked to the metallic cations in an axial position. The H-bonds occurring in the crystal structure result in the formation of 2D supramolecular chains and 3D networks. The Hirshfeld surface analysis of the complex has shown the presence of strong O-H...O and C-H...O hydrogen bonds together with non-classical weak C-H...pi, pi...pi, pi...lp/lp...pi and lp ...lp interactions. Furthermore, the theoretical calculations results are in agreement with the experimental geometric parameters. The NMR spectra and the MEP maps were also calculated.