Synthesis, crystal structure, spectroscopic, thermogravimetric and theoretical characterization of Ni(II) and Zn(II) complexes with 4-chloro-2-nitrobenzenesulfonamide

Two new complexes of Ni and Zn with 4-chloro-2-nitrobenzenesulfonamide (ClNbsa) have been synthesized and characterized. The structure of the [Ni(ClNbsa)2(NH3)4] complex was determined by X-ray diffraction methods. It crystallizes in the monoclinic P21/c space group with a = 12.8679(3) Å, b = 7.7254(1) Å, c = 12.2478(2) Å, β = 109.899(2)°, V = 1144.85 (4)Å3 and Z = 4 molecules per unit cell. The coordination geometry of the Nickel (II) ion in the complex can be described as a distorted octahedron with two N-sulfonamide and four NH3 groups in opposite vertices. Due to the poor solubility of the Zn(II) complex, their cell parameters were determined by indexing the powder X-ray pattern using the successive dichotomy method implemented in the Fullprof Suite software package. A triclinic cell was determined with cell parameters a = 18.3724(1) Å, b = 7.9468(8) Å, c = 10.2212(9) Å α = 63.061(6) β = 108.754(6) γ = 109.153(6) and V = 1229.97(2)Å3. Nuclear magnetic resonance (NMR) spectroscopy of 1H and 13C have been used for support the structure of the Zn complex. Vibrational and electronic spectroscopy have been used to characterize the compounds, using theoretical calculations for the assignment of the experimental bands. The thermal behavior was investigated by thermogravimetric analyses (TG) and differential thermal analysis (DT).