Calcium titanate

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Calcium titanate
CaTiO3 perovskite structure.png
Identifiers
CAS number 12049-50-2 YesY
PubChem 16212381
ChemSpider 17340234 YesY
RTECS number XR2568666
Jmol-3D images Image 1
Properties
Molecular formula CaTiO3
Molar mass 135.943 g/mol
Appearance white powder
Density 3.98 g/cm3
Melting point 1975 °C
Boiling point 3000 °C
Solubility in water insoluble
Hazards
LD50 >1200 mg/kg (oral, rat)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references
This article is about the chemical. For the mineral, see perovskite.

Calcium titanate, also known as calcium titanium oxide, is an inorganic compound with the chemical formula CaTiO3. As a mineral, it is called perovskite, named after Russian mineralogist, L. A. Perovski (1792-1856). It is a colourless, diamagnetic solid, although the mineral is often coloured owing to impurities.

Synthesis[edit]

CaTiO3 can be prepared by the combination of CaO and TiO2 at temperatures >1300 °C. Sol-gel processes has been used to make a more pure substance, as well as lowering the synthesis temperature. These compounds synthesized are more compressible due to the powders from the sol-gel process as well and bring it closer to its calculated density (~4.04 g/ml).[1][2]

Structure[edit]

Calcium titanate is obtained as orthorhombic crystals, more specifically perovskite structure.[3] In this motif, the Ti(IV) centers are octahedral and the Ca2+ centers occupy a cage of 12 oxygen centres. Many useful materials adopt related structures, e.g. barium titanate or variations of the structure, e.g. yttrium barium copper oxide.

Applications[edit]

Calcium titanate has relatively little value except as one of the ores of titanium, together with several others. It is reduced to give titanium metal or ferrotitanium alloys.[4]

See also[edit]

External links[edit]

References[edit]

  1. ^ Pfaff, G. (1994). "Synthesis of calcium titanate powders by the sol-gel process". Chemistry of Materials 6: 58. doi:10.1021/cm00037a013.  edit
  2. ^ Dunn, B.; Zink, J. I. (2007). "Sol–Gel Chemistry and Materials". Accounts of Chemical Research 40 (9): 729. doi:10.1021/ar700178b. PMID 17874844.  edit
  3. ^ R. H. Buttner, E. N Maslen: Electron difference density and structural parameters in CaTiO3. In: Acta Crystallographica. Nr. B48, 1992, S. 644-649.
  4. ^ Heinz Sibum, Volker Günther, Oskar Roidl, Fathi Habashi, Hans Uwe Wolf, "Titanium, Titanium Alloys, and Titanium Compounds" in Ullmann's Encyclopedia of Industrial Chemistry 2005, Wiley-VCH, Weinheim. doi:10.1002/14356007.a27 095