Influence of functionalities over polymer, trimer, dimer formation and optical properties of cadmium dithiocarbamates
作者:Krishna K. Manar、Manoj K. Yadav、Anamika、Michael G.B. Drew、Nanhai Singh
DOI:10.1016/j.poly.2016.06.047
日期:2016.10
Homoleptic cadmium(II) bis(dithiocarbamate) complexes having polymeric [Cd(L)(2)](infinity) (L = C(7)H(5)0(2)CH(2)NCS(2)CH(2)C(6)H(5) (L1), 1; C6H4NO2CH2NCS2CH2C4H3O (L2), 2; C6H4FCH2NCS2CH2C4H3O (L3), 3), trinuclear [Cd(L4)(2)](3) (L4 = 4-ClC6H4CH2NCS2CH2C4H3O, 4) and dinuclear [Cd(L5)(2)](2), (L5= 3-CIC6H4CH2NCS2CH2C6H5, 5) structures have been synthesized and characterized by elemental analyses, spectroscopy (IR, H-1 and C-13 H-1} NMR and UV-Vis.) and their structures have been revealed by X-ray crystallography. In 1-3 the dithiocarbamate ligands are uniquely bonded to the Cd atoms in a mu(2),kappa(2) S, S-chelating-bridging fashion, portraying 1D coordination polymeric structures in which the cadmium (II) ions adopt six coordinate distorted octahedral structures. In 4 the six dithiocarbamate ligands are spectacularly arranged about the Cd atoms resulting in a centrosymmetric trinuclear complex in which the central metal adopts an octahedral geometry and the terminal Cd atoms are in square pyramidal environments. Complex 5 has the well-established centrosymmetric dimeric structure in which the metal atoms have a five-coordinate trigonal bipyramidal geometry. Complexes 1-4 are rare examples of polymeric and trinuclear cadmium dithiocarbamate complexes. 1-5 show luminescent characteristics in solution and in the solid state arising from the metal perturbed intra-ligand charge transfer (ILCT) states. Their TG analyses show a single step decomposition with the formation of CdS nanoparticles, which have been examined by PXRD and HRTEM. (C) 2016 Elsevier Ltd. All rights reserved.