[{"@context":"http:\/\/schema.org\/","@type":"BlogPosting","@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/molybdenum-bronze-wikipedia\/#BlogPosting","mainEntityOfPage":"https:\/\/wiki.edu.vn\/en\/wiki24\/molybdenum-bronze-wikipedia\/","headline":"Molybdenum bronze – Wikipedia","name":"Molybdenum bronze – Wikipedia","description":"From Wikipedia, the free encyclopedia Generic name for certain mixed oxides of molybdenum “Purple bronze” redirects here. Not to be","datePublished":"2017-05-03","dateModified":"2017-05-03","author":{"@type":"Person","@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/author\/lordneo\/#Person","name":"lordneo","url":"https:\/\/wiki.edu.vn\/en\/wiki24\/author\/lordneo\/","image":{"@type":"ImageObject","@id":"https:\/\/secure.gravatar.com\/avatar\/c9645c498c9701c88b89b8537773dd7c?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/c9645c498c9701c88b89b8537773dd7c?s=96&d=mm&r=g","height":96,"width":96}},"publisher":{"@type":"Organization","name":"Enzyklop\u00e4die","logo":{"@type":"ImageObject","@id":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","url":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","width":600,"height":60}},"image":{"@type":"ImageObject","@id":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/3\/35\/KMoO3Bronze.JPG\/220px-KMoO3Bronze.JPG","url":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/thumb\/3\/35\/KMoO3Bronze.JPG\/220px-KMoO3Bronze.JPG","height":"165","width":"220"},"url":"https:\/\/wiki.edu.vn\/en\/wiki24\/molybdenum-bronze-wikipedia\/","about":["Wiki"],"wordCount":5237,"articleBody":"From Wikipedia, the free encyclopediaGeneric name for certain mixed oxides of molybdenum“Purple bronze” redirects here. Not to be confused with Hepatizon, a form of bronze which takes on a purple-colored patina.In chemistry, molybdenum bronze is a generic name for certain mixed oxides of molybdenum with the generic formula AxMoyOz where A may be hydrogen, an alkali metal cation (such as Li+, Na+, K+), and Tl+.  These compounds form deeply coloured plate-like crystals with a metallic sheen, hence their name.  These bronzes derive their metallic character from partially occupied 4d bands.[1] The oxidation states in K0.28MoO3 are K+1, O2\u2212, and Mo+5.72.  MoO3 is an insulator, with an unfilled 4d band.These compounds have been much studied since the 1980s due to their markedly anisotropic electrical properties, reflecting their layered structure.  The electrical resistivity can vary considerably depending on the direction, in some cases by 200:1 or more.  They are generally non-stoichiometric compounds.  Some are metals and some are semiconductors.Table of ContentsPreparation[edit]Classification[edit]Electrical and thermal properties[edit]See also[edit]References[edit]Preparation[edit]The first report of a “molybdenum bronze” was by Alfred Stavenhagen and E. Engels in 1895.  They reported that electrolysis of molten Na2MoO4 and MoO3 gave indigo-blue needles with metallic sheen, which they analysed by weight as Na2Mo5O7.[2] The first unambiguous synthesis of alkali molybdenum bronzes was reported only in 1964, by Wold and others.[3]  They obtained two potassium bronzes, “red” K0.26MoO3 and “blue” K0.28MoO3, by electrolysis of molten K2MoO4+MoO3 at 550 \u00b0C and 560\u00a0\u00b0C, respectively.  Sodium bronzes were also obtained by the same method. It was observed that at a slightly higher temperature (about 575\u00a0\u00b0C and above) only MoO2 is obtained.[3][4]Another preparation technique involves crystallization from the melt in a temperature gradient.  This report also called attention to the marked anisotropic resistivity of the purple lithium bronze Li0.9Mo6O17 and its metal-to-insulator transition at about 24 K.[5]Hydrogen bronzes HxMoO3 were obtained in 1950 by Glemser and Lutz, by ambient-temperature reactions.[6] The hydrogen in these compounds can be replaced by alkali metals by treatment with solutions of the corresponding halides.  Reactions are conducted in an autoclave at about 160\u00a0\u00b0C.[7]  Crystals of K0.28MoO3, also called “potassium-molybdenum blue bronze”.Classification[edit]Molybdenum bronzes are classified in three major families:[4][7]Red bronzes with limiting composition A0.33MoO3, that is, AMo3O9:[7]Blue bronzes, with limiting composition A0.30MoO3, that is, A3Mo10O30.[7] Their electronic properties generally do not depend on the metal A.[1]Purple bronzes, generally with limiting formula A0.9Mo6O17.  Their electronic properties depend strongly on the metal A.[1]The hydrogen molybdenum bronzes have similar appearances but different compositions:Other molybdenum bronzes with anomalous electrical properties have been reported, which do not fit in these families.  These includeElectrical and thermal properties[edit]This section is empty.  You can help by adding to it.  (March 2020)See also[edit]References[edit]^ a b c Onoda, M.; Toriumi, K.; Matsuda, Y.; Sato, M. (1987). “Crystal structure of lithium molybdenum purple bronze Li0.9Mo6O17“. Journal of Solid State Chemistry. Elsevier BV. 66 (1): 163\u2013170. doi:10.1016\/0022-4596(87)90231-3. ISSN\u00a00022-4596.^ Stavenhagen, A.; Engels, E. (1895). “Ueber Molybd\u00e4nbronzen”. Berichte der deutschen chemischen Gesellschaft. Wiley. 28 (2): 2280\u20132281. doi:10.1002\/cber.189502802213. ISSN\u00a00365-9496.^ a b c d e f Wold, A.; Kunnmann, W.; Arnott, R. J.; Ferretti, A. (1964). “Preparation and Properties of Sodium and Potassium Molybdenum Bronze Crystals”. Inorganic Chemistry. American Chemical Society (ACS). 3 (4): 545\u2013547. doi:10.1021\/ic50014a022. ISSN\u00a00020-1669.^ a b   Martha Greenblatt (1996), “Molybdenum and tungsten bronzes: Low-dimensional metals with unisial properties”. In C. Schlenker ed., “Physics and Chemistry of Low-Dimensional Inorganic Conductors” Book, Springer, 481 pages. ISBN\u00a09780306453045^ Greenblatt, M.; McCarroll, W.H.; Neifeld, R.; Croft, M.; Waszczak, J.V. (1984). “Quasi two-dimensional electronic properties of the lithium molybdenum bronze, Li0.9Mo6O17“. Solid State Communications. Elsevier BV. 51 (9): 671\u2013674. doi:10.1016\/0038-1098(84)90944-x. ISSN\u00a00038-1098.^ a b Glemser, Oskar; Lutz, Gertrud (1950). “\u00dcber ein Hydroxydhydrid des Molybd\u00e4ns”. Die Naturwissenschaften (in German). Springer Science and Business Media LLC. 37 (23): 539\u2013540. doi:10.1007\/bf00589341. ISSN\u00a00028-1042.^ a b c d e Chin, Kin; Eda, Kazuo; Sotani, Noriyuki; Whittingham, M.Stanley (2002). “Hydrothermal Synthesis of the Blue Potassium Molybdenum Bronze, K0.28MoO3“. Journal of Solid State Chemistry. Elsevier BV. 164 (1): 81\u201387. doi:10.1006\/jssc.2001.9450. ISSN\u00a00022-4596.^ a b c d Tsai, P.P.; Potenza, J.A.; Greenblatt, M.; Schugar, H.J. (1986). “Crystal structure of Li0.33MoO3, a stoichiometric, triclinic, lithium molybdenum bronze”. Journal of Solid State Chemistry. Elsevier BV. 64 (1): 47\u201356. doi:10.1016\/0022-4596(86)90120-9. ISSN\u00a00022-4596.^ a b c Whangbo, M. H.; Schneemeyer, L. F. (1986). “Band electronic structure of the molybdenum blue bronze A0.30MoO3 (A = K, Rb)”. Inorganic Chemistry. American Chemical Society (ACS). 25 (14): 2424\u20132429. doi:10.1021\/ic00234a028. ISSN\u00a00020-1669.^ Collins, B.T.; Ramanujachary, K.V.; Greenblatt, M.; Waszczak, J.V. (1985). “Charge-density wave instability and nonlinear transport in Tl0.3MoO3 a new blue molybdenum oxide bronze”. Solid State Communications. Elsevier BV. 56 (12): 1023\u20131028. doi:10.1016\/0038-1098(85)90863-4. ISSN\u00a00038-1098.^  E. Canadell and M.-H. Wangbo (1996), “Fermi surfaces instabilities in oxides and bronzes”. In C. Schlenker ed. (1996), “Physics and Chemistry of Low-Dimensional Inorganic Conductors” Book, Springer, 481 pages. ISBN\u00a09780306453045^ a b c d Birtill, J.J.; Dickens, P.G. (1979). “Thermochemistry of hydrogen molybdenum bronze phases HxMoO3“. Journal of Solid State Chemistry. Elsevier BV. 29 (3): 367\u2013372. doi:10.1016\/0022-4596(79)90193-2. ISSN\u00a00022-4596.^ Ramanujachary, K.V.; Greenblatt, D.M.; Jones, E.B.; McCarroll, W.H. (1993). “Synthesis and Characterization of a New Modification of the Quasi-Low-Dimensional Compound KMo4O6“. Journal of Solid State Chemistry. Elsevier BV. 102 (1): 69\u201378. doi:10.1006\/jssc.1993.1008. ISSN\u00a00022-4596.^ Andrade, Margareth; Maffei, Mariana Lanzoni; Alves, Leandro Marcos Salgado; Santos, Carlos Alberto Moreira dos; Ferreira, Bento; Sartori, Antonio Fernando (2012-10-11). “Microstructure and metal-insulator transition in single crystalline KMo4O6“. Materials Research. FapUNIFESP (SciELO). 15 (6): 998\u20131002. doi:10.1590\/s1516-14392012005000132. ISSN\u00a01980-5373.^ Alves, L. M. S.; Damasceno, V. I.; dos Santos, C. A. M.; Bortolozo, A. D.; Suzuki, P. A.; Izario Filho, H. J.; Machado, A. J. S.; Fisk, Z. (2010-05-26). “Unconventional metallic behavior and superconductivity in the K-Mo-O system”. Physical Review B. American Physical Society (APS). 81 (17): 174532. doi:10.1103\/physrevb.81.174532. ISSN\u00a01098-0121.  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