Potassium niobate

Potassium niobate (KNbO3) is a perovskite ferroelectric crystal. It has nonlinear optical coefficient properties, making it common in the manufacture of lasers.[2] Nanowires of potassium niobate have been used to produce tunable coherent light. The LD50 for potassium niobate is 3000 mg/kg (oral, rat).

Potassium niobate
Names
IUPAC name
Potassium niobate
Other names
niobate, niobium potassium oxide, potassium columbate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.031.573
Properties
KNbO3
Molar mass 180.003 g·mol−1
Appearance White rhombohedral crystals
Density 4.640 g/cm3
Melting point ≈ 1100 °C[1]
Hazards
Lethal dose or concentration (LD, LC):
3000 mg/kg (oral, rat)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Crystal Structure

On cooling from high temperature, KNbO3 undergoes a series of structural phase transitions. At 435 °C, the crystal symmetry changes from cubic centrosymmetric (Pm3 ̅m) to tetragonal non-centrosymmetric (P4mm). On further cooling, at 225 °C the crystal symmetry changes from tetragonal (P4mm) to orthorhombic (Amm2) and at −50 °C from orthorhombic (Amm2) to rhombohedral (R3m).

Use in research

Potassium niobate has been found useful in many different areas of materials science research,[3] including properties of lasers,[4] quantum teleportation,[5] and it has been used to study the optical properties of particulate composite materials.[6]

In addition to research in electronic memory storage,[3] potassium niobate is used in resonant doubling, a technique developed at the IBM Almaden Research Center.[4] This technique allows small infrared lasers to convert output into blue light, a critical technology for the production of blue lasers and technology dependent upon them.

References
  1. CRC Handbook, 90th Edition (03 Jun 2009) ISBN 1-4200-9084-4, section 4: Physical Constants of Inorganic Compounds, page 83
  2. Palik, Edward D. (1998). Handbook of Optical Constants of Solids 3. Academic Press. p. 821. ISBN 978-0-12-544423-1. Retrieved 13 December 2012.
  3. "In Science Fields". The Science News-Letter. 62 (17): 264–265. 1952-10-25. doi:10.2307/3931381. JSTOR 3931381. – via JSTOR (subscription required)
  4. Regalado, Antonio (1995-03-31). "Blue-Light Special". Science. New Series. 267 (5206): 1920. Bibcode:1995Sci...267.1920R. doi:10.1126/science.267.5206.1920. JSTOR 2886437. – via JSTOR (subscription required)
  5. Furusawa, A.; J. L. Sørensen; S. L. Braunstein; C. A. Fuchs; H. J. Kimble; E. S. Polzik (1998-10-23). "Unconditional Quantum Teleportation". Science. New Series. 282 (5389): 706–709. Bibcode:1998Sci...282..706F. doi:10.1126/science.282.5389.706. JSTOR 2899257. PMID 9784123. – via JSTOR (subscription required)
  6. Lakhtakia, Akhlesh; Tom G. Mackay (2007-02-08). "Electrical Control of the Linear Optical Properties of Particulate Composite Materials". Proceedings of the Royal Society A. 463 (2078): 583–592. arXiv:physics/0607274. Bibcode:2007RSPSA.463..583L. doi:10.1098/rspa.2006.1783. JSTOR 20209136. – via JSTOR (subscription required)
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.