Abstract

Tetrakis-μ-p-fluorobenzoatodicopper (II) was synthesized and spectroscopically characterized to have a binuclear, paddle-wheel structure with axially ligated ethanol molecules but with unexpectedly high magnetic moment value of 1.91 B.M. The complex was found to be thermally stable up to 280°C, and underwent three stages of decomposition process. The differential scanning calorimetric (DSC) curve showed three small endotherms at 100, 150 and 190°C respectively, agreeable to the TG analysis data, indicating the initial weight loss due to solvated molecules and the starting of a major decomposition process. Cyclic voltammetry studies of the complex, in mixed-solvent system of methanol and ethanoic acid (20:1 v/v) showed three cathodic peaks at -0.22, -0.35 and -0.86 V, representing step-wise electron transfer process and a single broad anodic peak at +0.39 V. The high value of ΔE ranging from 610 to 1250 mV indicated that the redox process was accompanied by extensive structural reorganization of the complex in the solution creating a different geometrical environment around central copper ion.

Key words: Copper (II) 4-fluorobenzoate, thermal stability, magnetic property, cyclic voltammetry.