Lithium oxide

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Lithium oxide
Lithium oxide
IUPAC name Dilithium oxygen(-2) anion
Other names Lithium monoxide
Lithia
Identifiers
CAS number [12057-24-8]
PubChem 166630
EINECS number 247-475-2
Properties
Molecular formula Li2O
Molar mass 29.881(4) gmol-1
Appearance white solid
Density 2.013 gcm-3
Melting point

1570 °C (1840 K)

Solubility in water Reacts
Hazards
NFPA 704
0
4
2
 
Related compounds
Other anions Lithium sulfide
Other cations Sodium oxide
Potassium oxide
Rubidium oxide
Related oxides Lithium peroxide
Lithium superoxide
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Lithium oxide (Li2O) or lithia is an inorganic chemical compound. Lithium oxide is formed along with small amounts of lithium peroxide when lithium metal is burned in the air and combines with oxygen[1]:

4Li+O2 → 2Li2O.

Pure Li2O can be produced by the thermal decomposition of lithium peroxide, Li2O2 at 450°C

2Li2O2 → 2Li2O + O2

Contents

[edit] Structure

In the solid state lithium oxide adopts an antifluorite structure which is related to the CaF2, fluorite structure with Li cations substituted for fluoride anions and oxide anions substituted for calcium cations.
The ground state gas phase Li2O molecule is linear with a bond length consistent with strong ionic bonding.[2][3] VSEPR theory would predict a bent shape similar to H2O.

[edit] Uses

Lithium oxide is used as a flux in ceramic glazes; and creates blues with copper and pinks with cobalt. Lithium oxide reacts with water and steam, and should be isolated from them.

Its usage is also being investigated for non-destructive emission spectroscopy evaluation and degradation monitoring within thermal barrier coating systems. It can be added as a co-dopant with yttria in the zirconia ceramic top coat, without a large decrease in expected service life of the coating. At high heat, lithium oxide emits a very detectable spectral pattern, which increases in intensity along with degradation of the coating. Implementation would allow in situ monitoring of such systems, enabling an efficient means to predict lifetime until failure or necessary maintenance.

[edit] See also

[edit] References

  1. ^ Greenwood, N. N.; Earnshaw, A. (1997). Chemistry of the Elements, 2nd Edition, Oxford:Butterworth-Heinemann. ISBN 0-7506-3365-4. 
  2. ^ Wells A.F. (1984) Structural Inorganic Chemistry 5th edition Oxford Science Publications ISBN 0-19-855370-6
  3. ^ A spectroscopic determination of the bond length of the LiOLi molecule: Strong ionic bonding, D. Bellert, W. H. Breckenridge, J. Chem. Phys. 114, 2871 (2001); doi:10.1063/1.1349424

[edit] External links