Chromium compounds: dichromium trioxide

chromium symbol icon

The chromium in dichromium trioxide formally is in the oxidation state 3.

Crystal structure of dichromium trioxide

Dichromium trioxide

  • Formula as often written: Cr2O3
  • Hill system formula: Cr2O3
  • CAS registry number: [1308-38-9]
  • Formula weight: 151.99
  • Class: oxide


  • dichromium trioxide
  • chromium(III) oxide
  • chromium oxide

Physical properties

  • Colour: green
  • Appearance: crystalline solid
  • Melting point: 2450°C; 2330°C
  • Boiling point: 3000°C
  • Density: 5200 kg m-3


Coming soon...

Element analysis

Element percentages for the elements in dichromium trioxide
Element %
Cr 68.42
O 31.58


Not available

Solid state structure

  • Geometry of chromium:
  • Prototypical structure:

Crystal structure of dichromium trioxide

Isotope pattern

What follows is the calculated isotope pattern for the Cr2O3 unit with the most intense ion set to 100%.

Formula: Cr2O3

mass  %
148   0.3 
149 0.0
150 10.3 _____
151 1.2 _
152 100.0 __________________________________________________
153 22.7 ___________
154 7.5 ____
155 0.8
156 0.1
157 0.0


The data on these compounds pages are assembled and adapted from the primary literature and several other sources including the following.

  • R.T. Sanderson in Chemical Periodicity, Reinhold, New York, USA, 1960.
  • N.N. Greenwood and A. Earnshaw in Chemistry of the Elements, 2nd edition, Butterworth, UK, 1997.
  • F.A. Cotton, G. Wilkinson, C.A. Murillo, and M. Bochmann, in Advanced Inorganic Chemistry, John Wiley & Sons, 1999.
  • A.F. Trotman-Dickenson, (ed.) in Comprehensive Inorganic Chemistry, Pergamon, Oxford, UK, 1973.
  • R.W.G. Wyckoff, in Crystal Structures, volume 1, Interscience, John Wiley & Sons, 1963.
  • A.R.West in Basic solid state chemistry Chemistry, John Wiley & Sons, 1999.
  • A.F. Wells in Structural inorganic chemistry, 4th edition, Oxford, UK, 1975.
  • J.D.H. Donnay, (ed.) in Crystal data determinative tables, ACA monograph number 5, American Crystallographic Association, USA, 1963.
  • D.R. Lide, (ed.) in Chemical Rubber Company handbook of chemistry and physics, CRC Press, Boca Raton, Florida, USA, 77th edition, 1996.
  • J.W. Mellor in A comprehensive treatise on inorganic and theoretical chemistry, volumes 1-16, Longmans, London, UK, 1922-1937.
  • J.E. Macintyre (ed.) in Dictionary of inorganic compounds, volumes 1-3, Chapman & Hall, London, UK, 1992.

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