Tungsten(III) oxide
IUPAC name
Tungsten(III) oxide
Other names
Tungsten sesquioxide
3D model (JSmol)
  • InChI=1S/3O.2W
  • O=[W]O[W]=O
Molar mass 415.68 g/mol
Density g/cm3
Related compounds
Tungsten trioxide
Tungsten(IV) oxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Tungsten(III) oxide (W2O3) is a compound of tungsten and oxygen. It has been reported (2006) as being grown as a thin film by atomic layer deposition at temperatures between 140 and 240 °C using W2(N(CH3)2)6 as a precursor.[1] It is not referred to in major textbooks.[2][3] Some older literature refers to the compound W2O3 but as the atomic weight of tungsten was believed at the time to be 92 (i.e., approximately half the modern accepted value of 183.84) the compound actually being referred to was WO3.[4]

Reports about the compound date back to at least the 1970s, but only in as thin films or surfaces – no bulk synthesis of the material is known.[5]


Tungsten(III) oxide is used in various types of infrared absorbing coatings and foils.[6]


  1. ^ Atomic Layer Deposition of Tungsten(III) Oxide Thin Films from W2(NMe2)6 and Water: Precursor-Based Control of Oxidation State in the Thin Film Material Charles L. Dezelah IV, Oussama M. El-Kadri, Imre M. Szilagyi, Joseph M. Campbell, Kai Arstila, Lauri Niinistö, Charles H. Winter, J. Am. Chem. Soc., 128 (30), 9638–9639, (2006)doi:10.1021/ja063272w
  2. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
  3. ^ Wells, A. F. (1984), Structural Inorganic Chemistry (5th ed.), Oxford: Clarendon Press, ISBN 0-19-855370-6
  4. ^ F. T Conington (1858), A handbook of chemical analysis, based on Dr. H. Will's Anleitung zur chemischen analyse, Longman, Brown, Green, Longmans, and Roberts
  5. ^ Becker, Nils; Reimann, Christoph; Weber, Dominik; Lüdtke, Tobias; Lerch, Martin; Bredow, Thomas; Dronskowski, Richard (2017-01-01). "A density-functional theory approach to the existence and stability of molybdenum and tungsten sesquioxide polymorphs". Zeitschrift für Kristallographie – Crystalline Materials. 232 (1–3). Walter de Gruyter GmbH: 69–75. doi:10.1515/zkri-2016-1960. ISSN 2196-7105. S2CID 67764349.
  6. ^ Willey, R.R. (2002), Practical Design and Production of Optical Thin Films. Available from: http://www.crcnetbase.com/isbn/9780203910467 CRC Press. Section: ISBN 978-0-203-91046-7 Accessed: 17-07-2014