Heteropoly blues of α-1,2 and α-1,4 isomers of [PV2W10O40]5−have been prepared by using the electrochemical technique. EPR spectra, measured as a function of temperature over a wide range (20-300 K), are explicable in terms of electron-hopping processes in heteropoly blues. Temperature dependence of A∥of the isomers suggest that the activation energy for electron hopping is greater for the α-1,4 isomer than the α-1,2 isomer. Other parameters like stability of the blues and intra-molecular electron transfer rate constants are also evaluated using EPR as the tool.
