Perovskite



 

Perovskite (crystal system. Perovskite was discovered in the Ural mountains of Russia by Gustav Rose in 1839 and named for Russian mineralogist, L. A. Perovski (1792-1856).

Perovskite is also the name of a more general group of crystals which take the same polymorph of MgSiO3, and may be the most common mineral in the Earth.[1]

Perovskite materials are used as catalyst electrodes in certain types of fuel cells.

Structure

The perovskite structure is adopted by many superconductors.

The general close-packed array, where the B ions occupy a quarter of the octahedral spaces.

Although the primitive cube is the idealized structure, differences in radius between the A and B cations can alter the structure to a number of different so-called distortions, of which tilting is the most common one. With perovskite tilt the BO6 octahedron twists along one or more axes to accommodate the difference.

Complex perovskite structures contain two different B-site cations. This results in ordered and disordered variants.

The perovskite structure shares the property of ferroelectricity with ceramic materials have perovskite-like structures.

Occurrences

Perovskite is found in contact metamorphic rocks and associated intrusives.

It is found in some carbonatites.

Perovskite also is a common mineral in the Ca-Al-rich inclusions (CAIs) found in some chondritic meteorites.

References

  1. ^ John Lloyd; John Mitchinson. "What's the commonest material in the world", QI: The Book of General Ignorance. Faber & Faber. ISBN 0-571-23368-6. 
  • Moty Schultz and Lior Klein, Physical Review B 73, 085109 (2006).
  • Tejuca, Luis G (1993). Properties and applications of perovskite-type oxides. New York: Dekker, 382. ISBN 0-8247-8786-2. 
  • Mitchell, Roger H (2002). Perovskites modern and ancient. Thunder Bay, Ontario: Almaz Press, 318. ISBN 0-9689411-0-9. 

See also

 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Perovskite". A list of authors is available in Wikipedia.