Available online at www.derpharmachemica.com Scholars Research Library Der Pharma Chemica, 2013, 5(5):82-87 (http://derpharmachemica.com/archive.html) ISSN 0975-413X CODEN (USA): PCHHAX 82 www.scholarsresearchlibrary.com DC conductivity studies of SrMe 2+ (Li 1+ Fe 3+ ) 0.5 Fe 16 O 27 ferrites P. R. Arjunwadkar, R. R. Patil and M. Y. Salunkhe* Govt. Institute of Science, R. T. Road, Nagpur, Maharashtra (India) _____________________________________________________________________________________________ ABSTRACT Lithium substituted W type ferrites having common chemical formula SrMe(LiFe) 0.5 -W where Me is a divalent cation such as Zn, Ni, Cd, Cu, Fe were prepared by standard solid state reaction method and their dc electrical properties such as conductivity, activation energy were studied and the type of carriers responsible in each was determined from thermoelectric studies. The higher resistivity of the compounds SrMe(LiFe) 0.5 W where Me = Cu, Zn and Ni, suggests less presence of mixed valency cations on equivalent lattice. While with Me = Fe and Cd show low value due to the ferrous ions present on the octahedral sites along with ferric ions. Keywords: W type ferrite, Lithium, Conductivity, Activation energy, Hopping. _____________________________________________________________________________________________ INTRODUCTION The critical literature survey revealed that the electrical properties of hexagonal [1,2,3] W-type ferrites are less studied compared to its magnetic properties. This may be due to the fact that they were developed initially as permanent magnet.[4,5,6,7] Today W-type ferrites are finding applications in many diverse fields like microwave and hence their electrical properties are also becoming important. Many attempts have been made to improve the properties of W ferrites by variety of substitutions. Though W-type ferrite does not contain any monovalent cation, hence a combination of monovalent cation with some multivalent cation for charge compensation may be substituted. With this idea in mind a new series of materials for permanent magnets BaZn 2(1-x) (LiFe) x W ferrites were developed for the first time by Mignot J. P. et. al.[8]. Afterward Ram S. and Joubert J.C.[9] reported synthesis and magnetic properties of SrZn 2 W ferrite using a partial 2Zn +2 = Li +1 Fe +3 substitution. Albanese G. et. al.[10] reported Mossbauer and magnetic study of SrZnLi 0.5 Fe 0.5 W ferrite along with thermoelectric analysis, X-ray diffraction and Mossbauer measurements. In the present work W type ferrites having common formula SrMe(LiFe) 0.5 -W where Me is a divalent cation such as Zn, Ni, Cd, Cu, Fe were prepared and their electrical properties such as conductivity, activation energy and thermoelectric power were studied. Since the properties of ferrite depend on the interactions among the cations distributed over various sites, these were explained on the basis of the knowledge of site distribution of cations in the W type structure. MATERIALS AND METHODS The W-type compounds, in the present investigations were prepared using the standard solid-state reaction method.[11,12] AR grade oxides and carbonates were used as starting materials. Preparation of ferrites from Hexagonal family are usually difficult as compared to Spinel ferrites and especially the W-type ferrite is one of the