W-type ferrite having chemical formula SrNi(LiFe)0.5Fe16O27 was prepared by using conventional solid state reaction method at little low temperature (1100°C). The prolonged and continuous heating resulted in better product formation and it has validated that the Lithium present in the compound facilitates the synthesis. Typical IR bands observed are assigned to the Fe–O bonds in S block of W ferrite structure and the band near 914.3？cm？1 is assigned to the stretching vibrations of Sr–O. High resistivity is found which suggested presence of very small amount of mixed valency cations on equivalent lattice apart from the little amount created due to the release of an electron by divalent Ni to become trivalent. The magnetic properties of compound do not differ much from those of the reported for SrNi2W ferrite except a little decrease in saturation magnetization at room temperature due to canting effect. The experimental observations support presumed site preferences to a greater extent and also the prediction that the Li present on sub-lattice results in small canting effect of 12k cations. The low value of coercivity observed is attributed to the larger particle size resulting due to prolonged heating. 1. Introduction The W-type hexagonal ferrites, having chemical formula Ba/SrM2Fe16O27 where M stands for divalent metal ion, belong to a very large family of hexagonal ferromagnetic oxides. The crystal structure of W-type ferrite has been described for the first time by Braun [1]. It can be considered as a stacking of R and S blocks along the hexagonal c axis: RSSR*S*S*…. The space group assigned for W-type ferrite is P63/mmc or (number 194) [2]. Because of the technological applications such as permanent magnets and microwave device materials, hexagonal ferrites are being studied. Among them, the W-type ferrites are investigated largely because of the different substitutions feasible by suitable choice of divalent metal ion [3–6]. W-type ferrite does not contain any monovalent cation, but a combination of monovalent cation with some multivalent cations for charge compensation may be substituted for the divalent metal ion. The critical literature survey showed that meagre work has been done in this direction except for the compound SrZn(LiFe)0.5Fe16O27 [7–10]. Ni substitution has found to play an important role in tailoring properties of ferrites and hence it was decided to investigate the electromagnetic properties of the compound having chemical formula SrNi(LiFe)0.5Fe16O27. As far as we know, the compound studied in the present investigations, is being
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