The crystal structure of BaTiO
3:CeO
2 was studied using the ESR spectrum of Fe
3+ ions, contaminating pure BaTiO
3, in the temperature range -160 degrees C to +160
degrees C. The observed powder spectra are classified into three
parts: pure, lightly doped (0.05-0.5 mole% CeO
2), and heavily doped (1-3 mole% CeO
2)BaTiO
3. The EPR spectrum of pure BaTiO
3 showed five resonance lines, at room temperature,
around g=2. On lowering the temperature, the five lines tend to
converge towards the central line. The lightly doped EPR spectra
reflected that the crystal fields experienced by Fe
3+ ions are highly inhomogeneous and g-values in all the
range g=12 to g=1.8 may be observed. The heavily doped samples
reflected an obvious stabilisation of crystal structure with
variation of temperature. The g-value reflected the effect of the
dopant concentration and showed little or no variation with
temperat...