Morphology and electrical conductivity of copper(II) 4-fluorobenzoate

Abstract

Copper(II) 4-fluorobenzoate (CFB), prepared from copper(II) acetate monohydrate and 4-fluorobenzoic acid, is a blue powder. The Fourier transform infrared spectrum of CFB, recorded as potassium bromide disc, indicates the presence of all bonds and functional groups expected of it. The X-ray diffraction pattern indicates that CFB is polycrystalline. The highest diffraction peak occurs at interplanar distance of 15.2 /spl Aring/, which corresponds to particle size of 450 /spl Aring/. Scanning electron microscopy of CFB shows that it has a layered structure. CFB conductivity at room temperature is 1.79/spl times/10/sup -11/ Scm/sup -1/. The value decreases as temperature increases in the temperature range 30-350 K, indicating metallic behaviour. The conduction mechanism obeys Mott's variable range hopping (VRH) model in the temperature range 140-350 K. The density of states at Fermi level based on the VRH model is 2.9/spl times/10/sup 26/ eV/sup -1/ cm/sup -3/. The hopping distance, hopping energy and density of charge carriers at 300 K are 0.73 /spl Aring/, 0.002 eV and 7.53/spl times/10/sup 24/ cm/sup -3/, respectively.