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Yttrium(III) oxide
Image:Yttrium(III) oxide.jpg
General
Systematic name	Yttrium(III) oxide.
Other names	Yttria, diyttrium trioxide
Molecular formula	Y2O3
Molar mass	225.81 g/mol
Appearance	White solid.
CAS number	[1314-36-9]
Properties
Density and phase	5.010 g/cm3, solid
Solubility	insoluble in water soluble in alcohol soluble in acids insoluble in alkalis.
Stability	Slightly hygroscopic
Melting point	2690 °C
Boiling point	4300 °C
Structure
Coordination geometry	Octahedral
Crystal structure	Hexagonal
Thermodynamic data
Standard enthalpy of formation ΔfH°solid	? kJ/mol
Standard molar entropy S°solid	? J.K−1.mol−1
Hazards
EU classification	None listed.
R-phrases	Not hazardous
S-phrases	S24/25
EU classification	None listed.
RTECS	ZG3850000
NFPA 704
Supplementary data page
Structure and properties	n, εr, etc.
Thermodynamic data	Phase behaviour Solid, liquid, gas
Spectral data	UV, IR, NMR, MS
Related compounds
Other anions	?
Other cations	Scandium(III) oxide, Lanthanum(III) oxide
Related compounds	Yttrium barium copper oxide
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Yttrium oxide is Y₂O₃. It is an air-stable, white substance. Yttrium oxide is used as a common starting material for both material science as well as inorganic compounds.

Contents 1 Uses 1.1 In material science 1.2 In inorganic synthesis 2 External links

[edit] Uses

[edit] In material science

It is the most important yttrium compound and is widely used to make YVO₄ europium and Y₂O₃ europium phosphors that give the red color in color TV picture tubes. Yttrium oxide is also used to make yttrium-iron-garnets, which are very effective microwave filters.

In its most important application, Y₂O₃ is used to make the high temperature superconductor YBa₂Cu₃O₇, known as "1-2-3" to indicate the ratio of the metal constituents:

0.5 Y₂O₃ + 2 BaO + 3 CuO + 0.25 O₂ → YBa₂Cu₃O₇

This synthesis is typically conducted at 800 °C.

[edit] In inorganic synthesis

Yttrium oxide is an important starting point for inorganic compounds. For organometallic chemistry it is converted to YCl₃ in a reaction with concentrated hydrochloric acid and ammonium chloride.

[edit] External links

• Yttrium oxide information at Webelements.
• External MSDS Data Sheet.
• Link page to external chemical sources.