Gamma ray irradiated binuclear and mononuclear transition metal complexes with polydentate ligand: Template synthesis, spectral, XRD, morphology, solid electrical conductivity and antimicrobial activity

Abstract

In this work, new binuclear Fe(III), Ni(II) and mononuclear Cu(II) Schiff base complexes that obtained via template condensation of Fe(III), Ni(II) and Cu(II) chlorides with N1-(3-aminopropyl) propane-1,3-diamine and 1,3-diphenylpropane-1,3‑dione (1B, 2B, 3B), respectively were prepared and well investigated. The structure of the complexes was elucidated by means of microanalyses, various spectroscopic techniques (FT–IR, UV/Vis, X–ray diffraction), thermal (TG/DTG), molar conductivity and magnetic moment measurements, Fe(III), Ni(II) complexes have an octahedral structure, while Cu(II) complex adopts distorted square pyramidal geometry. To study γ– irradiation induced modifications, powder sample of these complexes was exposed to high energetic γ–ray irradiation at a dose of 20 kGy, (hereafter referred to as 1A, 2A, 3A, respectively). Physico-chemical properties of irradiated samples were also investigated by the aforementioned tools. The results revealed no remarkable change in the molar conductivity values and little shift of the peak position and the intensity for FT–IR and electronic spectra as a result of the distortion of lattice planes. Also, TG/DTG studies revealed decreasing in the thermal stability for all irradiated samples. From the powder XRD data for non-irradiated and γ–irradiated Ni(II) (2B, 2A) and Cu(II) (3B, 3A) complexes, average crystallite size (D) and dislocation density (δ) were calculated, the γ–irradiation resulted in decrease in the crystallite size for Ni(II) (2A) complex. The irradiated (3A) showed changes in the surface morphology compared to its non-irradiated one. The solid state electrical conductivity of non-irradiated and γ–irradiated Ni(II) complexes have been investigated. Furthermore, the non-irradiated samples (1B, 3B) and their γ–irradiated (1A, 3A) were assayed for their antibacterial property against Gram–positive as Staphylococcus aureus, Gram– negative as Escherichia coli and antifungal property against fungi as Candida albicans.