The Crystal Structure of <i>trans</i>-Diaquo-bis(pyridine-2-carboxamide)-nickel(II) Chloride, [Ni(H2O)2(piaH)2]Cl2

Abstract

Abstract The crystal structure of trans-diaquo-bis(pyridine-2-carboxamide)nickel(II) chloride, [Ni-(H2O)2(piaH)2]Cl2, was determined by X-ray diffraction and refined by three-dimensional least-squares method. The crystals are monoclinic with space group P21⁄a, a=13.567, b=10.067, c=6.355 Å and β=113.73°. There are two formula units in the unit cell. The structure is built up of centrosymmetric complex ions and chloride ions. Two ligand molecules are coordinated to the nickel atom in trans position with amide oxygen atoms and ring nitrogen atoms. (Ni–N, 2.02 Å, Ni–O, 2.05 Å). The ligand molecules are nearly planar and they are approximately in one plane with the nickel atom. Two water molecules are coordinated at a distance of 2.14 Å and complete the octahedral arrangement around the nickel atom.