High-Pressure X-Ray Diffraction and Raman Scattering of LiTaO₃

We study the energy-dispersive x-ray diffraction and Raman
scattering of LiTaO₃ at high pressure. The result keeps stable up to 36 GPa. The average isothermal bulk modulus and its pressure derivative are obtained to be k₀ = (225±6) GPa and k｀₀ = 1.3±0.5 at zero pressure by the Birch-Murnaghan equation of state and the “universal”equation of state. The linear incompressibility of LiTaO₃ between the a- and c-directions differs by a factor of four, which shows that the compression is anisotropic.