Two new oxides, La₂Ba₂CaZn₂Ti₃O₁₄ and Pr₂Ba₂CaZn₂Ti₃O₁₄, have been synthesized by the ceramic route at 1100°C. These oxides crystallize in the disordered cubic structure with an ‘a’ lattice parameter of 3.9728 (2) and 3.9448 (5) respectively. These oxides show high dielectric constant (70 and 57) and low loss (0.003 and 0.013 at 100 kHz) for La₂Ba₂CaZn₂Ti₃O₁₄ and Pr₂Ba₂CaZn₂Ti₃O₁₄ respectively. The dielectric constant is highly stable with frequency and temperature.

Using molten salt route (with NaCl/KCl as the salt) we have been able to synthesize a new form of magnesium tantalate at 850°C. Powder X-ray diffraction data could be inde_xed on an orthorhombic unit cell with lattice parameters, ‘a’ = 15.36(1) Å, ‘b’ = 13.38(1) Å and ‘c’ = 12.10(1) Å. High resolution transmission electron microscopy and electron diffraction studies confirm the results obtained by X-ray studies. Energy dispersive X-ray spectroscopy helps ascertain the composition of MgTa₂O₆. The title compound shows a dielectric constant of ∼24 with a low dielectric loss of 0.006 at 100 kHz at room temperature. Dielectric constant is nearly unchanged with rise in temperature while the loss shows a very marginal increase (0.007 at 300°C).

Nanoparticles of complex manganites (viz. LaMnO₃, La_0.67Sr_0.33MnO₃ and La_0.67Ca{0.33}MnO₃) have been synthesized using the reverse micellar route. These manganites are prepared at 800‡C and the monophasic nature of all the oxides has been established by powder X-ray diffraction studies. TEM studies show an average grain size of 68, 80 and 50 nm for LaMnO₃, La_0.67Sr_0.33MnO₃ and La_0.67Ca{0.33}MnO₃respectively. Ferromagnetic ordering is observed at around 250 K for LaMnO₃, 350 K for La_0.67Sr_0.33MnO₃ and 200 K for La_0.67Ca{0.33}MnO₃. These Curie temperatures correspond well with those reported for bulk materials with similar composition.

Sub-micron rods and spheres of cobalt succinate sesquihydrate and iron succinate trihydrate/pentahydrate respectively have been synthesized by the reverse micellar route. These precursors are an excellent source for the synthesis of metal and metal oxide nanoparticles. Cubes of (edge length ∼ 150 nm) Fe₃O₄ and elongated particles of Fe₂O₃ (∼ diameter of 200 nm) were obtained. The role of oxidation state of the metal ion in controlling the morphology of the nanostructured dicarboxylates has been investigated. Rods with shorter length were obtained when longer chain dicarboxylate was used as ligand. Heating in nitrogen atmosphere also provided pure Co and 𝛼-Fe nanoparticles. The Fe nanoparticles show nearly 100% superparamagnetism. Temperature-dependent magnetic studies show a Morin-like transition for Fe₂O₃ nanoparticles at 223 K and the Verwey transition at 115 K for Fe₃O₄ nanoparticles. Co₃O₄ nanoparticles showed antiferromagnetic ordering at 20 K.