Title: Barium Titanate(IV)
CAS Registry Number: 12047-27-7
CAS Name: Barium titanium oxide (BaTiO3)
Additional Names: barium metatitanate
Molecular Formula: BaO3Ti
Molecular Weight: 233.19
Percent Composition: Ba 58.89%, O 20.58%, Ti 20.53%
Line Formula: BaTiO3
Literature References: Usually prepd by calcining (at about 1300°) an intimate mixture of titanium dioxide and barium carbonate. Prepn from Ti oxalate and a barium compd: Lynd, Merker, US 2758911 (1956 to National Lead). Wet process by the addn of a titanium ester, such as tetrapropyl titanate, to an aq soln of barium hydroxide: Flaschen, J. Am. Chem. Soc. 77, 6194 (1955). Prepn of high purity material by ignition of barium titanyloxalate: Clabaugh et al., J. Res. Natl. Bur. Stand. 56, 289 (1956). Prepn by ignition of Ba and Ti alcoholates in an organic solvent: DiVita, Fischer, US 2985504 (1961 to U.S. Dept. of the Army).
Properties: Exists in five cryst modifications. The tetragonal form (obtained by the wet process) appears to have the most desirable electric properties and is described here: d 6.08. mp 1625°. Curie point 120°. Has ferroelectric and piezoelectric properties. Becomes permanently polarized when exposed to high voltage direct current, provided the temperature is never allowed to rise above Curie pt. Has high dielectric properties which can be influenced by temp, voltage, and frequency.
Melting point: mp 1625°
Density: d 6.08
Use: In electronic devices, e.g., as voltage-sensitive dielectric in so-called dielectric amplifiers, in computer elements, magnetic amplifiers, memory devices. |