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White crystalline solid; exists in five crystal modifications; the common 94 BARIUM TITANATE tetragonal form has a Curie point of 120°C; exhibits ferroelectric and piezoelectric properties; density 6.02 g/cm3; melts at 1,625°C; insoluble in water and alkalies; slightly soluble in dilute mineral acids; dissolves in concentrated sulfuric acid and hydrofluoric acid.

The space lattice of BaTiO 3 takes four types of crystal systems, depending on temperatures. The trigonal crystal (lower than -90℃) shows the spontaneous polarization to the [111] direction.The rhombic crystal (-70℃ to 5℃) shows the spontaneous polarization to the [011] direction and takes a longer structure along the direction. The tetragonal crystal (5℃–120℃) shows the spontaneous polarization to the [001] direction and takes a longer structure along the direction by the ratio of c/a=1.01. The cubic crystal (higher temperature than Curie point 120℃) takes the calcium titanate structure (Perovskite structure) and Ba atoms position at the eight corners of the cube, six O atoms at the center of the planes, and a Ti atom at the center of the body.