Synthesis, spectroscopic, structural, DFT and antibacterial studies of cyclometalated rhodium(III) complex based on morpholinedithiocarbamate ligand

In this work, structural and spectroscopic properties of the cyclometalated Rh(III) complex, [Rh(ppy)(2)(Mdtc)]center dot H2O with ppy = 2-phenylpyridine and Mdtc = morpholine-4-dithiocarbamate were studied by X-ray crystallography and IR, H-1 and C-13 NMR, electronic absorption and Fluorescence spectroscopy. The title complex crystallized in triclinic, space group P-1, Z = 2, a = 9.7173(19) angstrom, b = 11.399(2) angstrom, c = 12.398(3) angstrom and alpha = 107.63(3); beta = 100.76 (3)degrees, gamma = 90.84(3)degrees Electronic spectrum of the complex show that ligand-centered (LCT) transitions and ligand-to-metal charge transfer (LMCT). Geometric structure, frontier orbital and electronic absorption spectrum property of the compound were investigated by using density functional theory (DFT) and compared with the experimental data. Calculated geometric parameters agree with the experimental data. Then the agar disc diffusion method was used to determine the antibacterial activity of the ligands and complex on the growth profile of Four Gram-negative bacteria, i.e., Pseudomunas aeroginosa, Salmonella typhai, Proteus mirabilis and Yersinia enterocolitica and two Gram-positive bacteria, i.e., Staphylococcus aureus and Enterococcus faecalis. The activity of the Rh (III) complex against bacteria was considerably stronger than the ligands.