Temperature and frequency dependent electrical transport in thiourea and tris (thiourea) copper (I) sulphate

The d.c. conductivity of thiourea and tris (thiourea) copper sulphate have been measured as a function of temperature, including their phase transitio n temperatures. The thermal activation energy values obtained showed that t he two compounds behaved as semiconducting materials. The mechanism of the conductivity was interpreted in the light of their molecular spectroscopic data in the infrared, ultraviolet and visible regions. The semiconducting p roperties of the ligand (TU) arise as a result of electron-delocalization v ia pi-bond formation (C=NH, C=NH2+), the hydrogen transfer and the highly p olar resonance hybride structural formation, and are altered by the copper ion in copper (TU) complex. The a.c. conductivity was measured at room temp erature. (C) 1999 Kluwer Academic Publishers.