Molybdenum blue

Molybdenum blue is a term applied to:

reduced heteropolymolybdate complexes, polyoxometalates containing Mo(V), Mo(VI), and a hetero atom such as phosphorus or silicon
reduced isopolymolybdate complexes, polyoxometalates containing Mo(V), Mo(VI) formed when solutions of Mo(VI) are reduced
a blue pigment containing molybdenum(VI) oxide

The "heteropoly-molybdenum blues", are used extensively in analytical chemistry and as catalysts. The formation of "isopoly-molybdenum blues" which are intense blue has been used as a sensitive test for reducing reagents. They have recently been shown to contain very large anionic species based on the so-called "big wheel" containing 154 Mo atoms, with a formula [Mo₁₅₄O₄₆₂H₁₄(H₂O)₇₀]¹⁴⁻.^[2]

The molybdenum blue pigment is historically documented^[3] but may not be in use today.

^ John R. Shapley (2004). Inorganic Syntheses, Vol 34. John Wiley & Sons, Inc. p. 197. ISBN 978-0-471-64750-8.
^ From Scheele and Berzelius to MÜller: polyoxometalates (POMs) revisited and the "missing link" between the bottom up and top down approaches P. Gouzerh, M. Che; L'Actualité Chimique, 2006, 298, 9
^ A Dictionary of Arts, Manufactures, and Mines: Containing a Clear Exposition of Their Principles, Andrew Ure, Published 1844, D. Appleton & Co.

[InorgSyn-1] John R. Shapley (2004). Inorganic Syntheses, Vol 34. John Wiley & Sons, Inc. p. 197. ISBN 978-0-471-64750-8.

[gouzerh-2] From Scheele and Berzelius to MÜller: polyoxometalates (POMs) revisited and the "missing link" between the bottom up and top down approaches P. Gouzerh, M. Che; L'Actualité Chimique, 2006, 298, 9

[Ure-3] A Dictionary of Arts, Manufactures, and Mines: Containing a Clear Exposition of Their Principles, Andrew Ure, Published 1844, D. Appleton & Co.

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