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Lithium oxide

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Lithium oxide
Names
IUPAC name
Lithium oxide
Other names
Lithium monoxide
Lithia
Identifiers
ECHA InfoCard 100.031.823 Edit this at Wikidata
RTECS number
  • OJ6360000
Properties
Li
2
O
Molar mass 29.88 g/mol
Appearance white solid
Density 2.013 g/cm3
Melting point 1,570 °C (2,860 °F; 1,840 K)
decomposes
6.67 g/100 mL (0 °C)
10.02 g/100 mL (100 °C)
log P 9.23
1.644 [1]
Structure
Antifluorite (cubic), cF12
Fm3m, No. 225
Tetrahedral (Li+); cubic (O2–)
Thermochemistry
18.105 J/g K
-20.01 kJ/g
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Corrosive, reacts violently with water
Flash point Non-flammable
Related compounds
Other anions
Lithium sulfide
Other cations
Sodium oxide
Potassium oxide
Rubidium oxide
Caesium oxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Lithium oxide (Li
2
O) 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[2]:

4Li+O
2
→ 2Li
2
O
.

Pure Li
2
O
can be produced by the thermal decomposition of lithium peroxide, Li
2
O
2
at 450°C[2]

2Li
2
O
2
→ 2Li
2
O
+ O
2

Structure

In the solid state lithium oxide adopts an antifluorite structure which is related to the CaF
2
, fluorite structure with Li cations substituted for fluoride anions and oxide anions substituted for calcium cations.[3]

The ground state gas phase Li
2
O
molecule is linear with a bond length consistent with strong ionic bonding.[4][5] VSEPR theory would predict a bent shape similar to H
2
O
.

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, forming lithium hydroxide 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.

A possible new use is as a replacement for lithium cobalt oxide as the cathode in the lithium ion batteries used to power electronic devices from mobile phones to laptop computers to battery-powered cars.[6]

See also

References

  1. ^ Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw-Hill, 2002, ISBN 0070494398
  2. ^ a b Greenwood, Norman N.; Earnshaw, Alan (1984). Chemistry of the Elements. Oxford: Pergamon Press. pp. 97–99. ISBN 978-0-08-022057-4.
  3. ^ Zintl, E.; Harder, A.; Dauth B. (1934). "Gitterstruktur der oxyde, sulfide, selenide und telluride des lithiums, natriums und kaliums". Z. Elektrochem. Angew. Phys. Chem. 40: 588–93. {{cite journal}}: line feed character in |journal= at position 68 (help)CS1 maint: multiple names: authors list (link)
  4. ^ Wells A.F. (1984) Structural Inorganic Chemistry 5th edition Oxford Science Publications ISBN 0-19-855370-6
  5. ^ 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
  6. ^ "Air power". The Economist, Technology Quarterly. September 3, 2009. Retrieved September 9, 2009.