Potassium tungsten bronzes

Lithium Potassium Tungsten Bronze, Li2W50j5.3K2W40i2, is... 

The M-NM transition has been a topic of interest from the days of Sir Humphry Davy when sodium and potassium were discovered till then only high-density elements such as Au, Ag and Cu with lustre and other related properties were known to be metallic. A variety of materials exhibit a transition from the nonmetallic to the metallic state because of a change in crystal structure, composition, temperature or pressure. While the majority of elements in nature are metallic, some of the elements which are ordinarily nonmetals become metallic on application of pressure or on melting accordingly, silicon is metallic in the liquid state and nonmetallic in the solid state. Metals such as Cs and Hg become nonmetallic when expanded to low densities at high temperatures. Solutions of alkali metals in liquid ammonia become metallic when the concentration of the alkali metal is sufficiently high. Alkali metal tungsten bronzes... 

Two potassium sodium tungsten bronzes have been prepared (see abo% e), 5K2W40i2.2Xa4 Vs0j 5 and Both are... 

Potassium Substituted SBN Thin Films. For SBN film synthesis, the crystallization of ferroelectric tungsten bronze phase on substrates encounters the problem of the formation of a low temperature phase. In order to prepare tungsten bronze thin films at lower temperatures, the substitution ofK+ forSr + or site is investigated (Sakamoto, 1996, 1997). 

Magneli, A. Studies on the hexagonal tungsten bronzes of potassium, rubidium and cesium., 4cta Chem. Scand 1953, 7, 315-324. 

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