Synthesis, characterization and dielectric properties of [Ru(SO3)(bpy)2(TCNX)] complexes
摘要:
Na[Ru(SO3)(TCNQ)(bpy)(2)] and [Ru(SO3)(bpy)(2)(TCNE)] complexes were synthesized and characterized by means of electrochemical techniques and electronic, vibrational and electron paramagnetic resonance (EPR) spectroscopies. Vibrational data indicated a metallocyclopropane configuration for TCNE while TCNQ ligand is coordinated through the nitrile fragment. EPR data indicated the reduced state for the metal centers and for the TCNQ ligand (TCNQ(-)). The values of the potentials assigned to the redox processes associated to the TCNX ligands indicated a decrease in the electron transfer barrier. Data of dielectric measurements hinted that TCNQ containing complex is more polarized than the TCNE containing compound. Impedance spectroscopy measurements indicated a temperature-dependent relaxation process for both the complexes. However, for TCNQ containing complex, the results suggested the transition from long-range to short-range mobility. In addition, two values of activation energy (2.0 and 0.6 eV) were calculated for this complex suggesting a phase transition process. (C) 2013 Elsevier Ltd. All rights reserved.
Synthesis, characterization and dielectric properties of [Ru(SO3)(bpy)2(TCNX)] complexes
摘要:
Na[Ru(SO3)(TCNQ)(bpy)(2)] and [Ru(SO3)(bpy)(2)(TCNE)] complexes were synthesized and characterized by means of electrochemical techniques and electronic, vibrational and electron paramagnetic resonance (EPR) spectroscopies. Vibrational data indicated a metallocyclopropane configuration for TCNE while TCNQ ligand is coordinated through the nitrile fragment. EPR data indicated the reduced state for the metal centers and for the TCNQ ligand (TCNQ(-)). The values of the potentials assigned to the redox processes associated to the TCNX ligands indicated a decrease in the electron transfer barrier. Data of dielectric measurements hinted that TCNQ containing complex is more polarized than the TCNE containing compound. Impedance spectroscopy measurements indicated a temperature-dependent relaxation process for both the complexes. However, for TCNQ containing complex, the results suggested the transition from long-range to short-range mobility. In addition, two values of activation energy (2.0 and 0.6 eV) were calculated for this complex suggesting a phase transition process. (C) 2013 Elsevier Ltd. All rights reserved.