Phase stability and equilibria in the La2O3–TiO2 system

XRD, electron probe wavelength and energy dispersive X-ray analyses were used to reexamine the phase relations in the La2O3–TiO2 system. The diagram was redrawn to include the compound La4Ti3O12 in addition to La4Ti9O24, La2Ti2O7 and La2TiO5. Above 1455°C a cation deficient perovskite La2/3TiO3 is stabilized by a small number of Ti3+ ions and remains stable on cooling in air. The proposed diagram represents a section through the system at the normal oxygen pressure in air at 1 atm, compositions being expressed in terms of the oxide components stable at room temperature.