  CaxCu3Ti4O12 polycrystalline powders with variation in calcium content were
prepared via the oxalate precursor route. The structural, morphological and
dielectric properties of the ceramics fabricated using these powders were
studied using x ray diffraction, Scanning Electron Microscope along with Energy
Dispersive X ray Analysis, Transmission Electron Microscopy, Electron Spin
Resonance (ESR) spectroscopy and Impedance analyzer. The X ray diffraction
patterns obtained for the x = 0.97, 1.0 and 1.1 powdered ceramics could be
indexed to a body centered cubic perovskite related structure associated with
the space group Im3. The ESR studies confirmed the absence of oxygen vacancies
in the ceramics that were prepared using the oxalate precursor route. The
dielectric properties of these suggest that the calcium deficient sample (x=
0.97) has a reduced dielectric loss while retaining the high dielectric
constant which is of significant industrial relevance.
