Manganese violet

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Manganese violet
Manganese violet.jpg
Identifiers
CAS number 10101-66-3
Properties
Molecular formula H4NMnO7P2
Molar mass 246.885
Appearance violet solid
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Manganese violet is the inorganic compound called ammonium manganese(III) pyrophosphate. The formula indicates that pyrophosphate (P2O74-), ammonium (NH4+), and manganese(III) make up this solid. It is prepared by heating a mixture of Mn2O3, diammonium phosphate and phosphoric acid. This material is a popular inorganic pigment.[1]

Chemical structure[edit]

Two polymorphs are known, referred to as the α- and β-forms, but in each case the structures are similar. The Mn(III) centres occupy distorted octahedral sites, being surrounded by six oxygens provided by the pyrophosphate ligands.[2]

References[edit]

  1. ^ Hugo Müller, Wolfgang Müller, Manfred Wehner, Heike Liewald "Artists' Colors" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a03_143.pub2
  2. ^ Yasmin Begum, Adrian J. Wright "Relating highly distorted Jahn–Teller MnO6 to colouration in manganese violet pigments" J. Mater. Chem., 2012, vol. 22, pp. 21110–21116. doi:10.1039/c2jm33731b