The electrical conductivity of some diamine complexesof the' general formula (CH2)n(NH3hMCI4_4r Yx, [x = 0, 2 & n = 2, 3 & M = Cu, Co and Y = Br, I]

Abstract

The dc and ac electrical conductivity for the compounds EDACoCI4 and EDACuCI4 [EDA = (CH2h(NH3hJ have been measured. The measurements were carried out as a function of temperature and frequency. By increasing the frequencies. the activation energy decreases due to increase in the conduction state of the system. The activation energy values for the compound EDACuCI4 is greater than those for EDACoC14 due to the ionization potential. By varying the organic cation from EDA to PDA. henceforth (CH2)3(NH3h. and inrroducmg two Br" or I- ions to become - C12Br1or C1112,we find that by increasing the size of halogen ions, the conductivity is directly affected due to electron affinity and electronegativity variation from one halogen to another. In both PDACuCl2BrZ and PDACuClzl2 the Br ' or 1- ions take the out of plane position. This affect the canting angle of the system as well as the inter and Intra-layer exchange interaction which are in direct correlation with the conductivity mechanism. The charge carrie: mobility is expected to keep constant in case of PDACuCl212 while it is increased in case of PDACuCI2Br2 complex.