Aluminium compounds: aluminium oxide (α)

aluminium symbol icon

The aluminium in aluminium oxide (α) formally is in the oxidation state 3.

Crystal structure of aluminium oxide (α)

Aluminium oxide (α)

  • Formula as often written: Al2O3
  • Hill system formula: Al2O3
  • CAS registry number: [1344-28-1]
  • Formula weight: 101.961
  • Class: oxide


  • aluminium oxide (α)
  • aluminium(III) oxide
  • aluminium oxide
  • aluminum oxide
  • aluminum oxide (α)
  • aluminum(III) oxide
  • corundum
  • dialuminium trioxide
  • dialuminum trioxide
  • α-alumina
  • α-aluminium oxide
  • α-aluminum oxide

Physical properties

  • Colour: white
  • Appearance: crystalline solid
  • Melting point: 2054°C
  • Boiling point: 3000°C
  • Density: 4000 kg m-3


This compound is available from Abbey Chemicals in the UK.

Element analysis

Element percentages for the elements in aluminium oxide (α)
Element %
Al 52.93
O 47.07


Not available

Solid state structure

  • Geometry of aluminium: 6 coordinate: octahedral
  • Prototypical structure:

Crystal structure of aluminium oxide (α)

Isotope pattern

What follows is the calculated isotope pattern for the Al2O3 unit with the most intense ion set to 100%.

Formula: Al2O3

mass  %
102 100.0 __________________________________________________
103 0.1
104 0.6


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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