WebElements Periodic Table of the Elements | Caesium

Caesium compounds: dicaesium oxide

The caesium in dicaesium oxide formally is in the oxidation state 1.

Dicaesium oxide

Formula as often written: Cs₂O
Hill system formula: Cs₂O₁
CAS registry number: [20281-00-9]
Formula weight: 281.81
Class: oxide

Synonyms

dicaesium oxide
caesium(I) oxide
cesium(I) oxide
dicesium oxide

Physical properties

Colour: yellow to orange
Appearance: crystalline solid
Melting point: 490°C
Boiling point:
Density: 4650 kg m^-3

Suppliers

Coming soon...

Element analysis

Element percentages for the elements in dicaesium oxide
Element	%
Cs	94.32
O	5.68

Synthesis

If caesium is burned in air, the result is mainly formation of orange caesium superoxide, CsO₂. The resulting CsO₂ can be converted into Cs₂O by the careful reaction of CsO₂ with caesium metal under nitrogen.

Cs(s) + O₂(g) → CsO₂(s)

CsO₂(s) + 3Cs(s) → 2Cs₂O(s)

Solid state structure

Geometry of caesium: 3 coordinate: pyramidal
Prototypical structure:

Crystal structure of dicaesium oxide

Isotope pattern

What follows is the calculated isotope pattern for the Cs₂O unit with the most intense ion set to 100%.

Formula: Cs₂O₁

mass  %
282 100.0 __________________________________________________
283   0.0 
284   0.2

References

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.