The influence of high hydrostatic pressure on lattice parameters of a single crystal of BaTiO₃

The lattice parameters of a single-crystal of BaTiO₃ have been measured under high hydrostatic pressure up to 5 GPa using a diamond-anvil high-pressure cell of a new design. The lattice becomes cubic at 2.08 (8) GPa and stays cubic at higher pressures. The pressure dependence of the tetragonal-cubic transition temperature is estimated to be -46 K GPa^-1.