Gallium(I) oxide

Gallium(I) oxide, digallium monoxide or gallium suboxide is an inorganic compound with the formula Ga₂O.

Gallium(I) oxide

Names
Other names gallium suboxide digallium monoxide
Identifiers
CAS Number	12024-20-3 Y
3D model (JSmol)	Interactive image
ChemSpider	34990294 Y
PubChem CID	16702109
UNII	EJS6TG9SIN Y
CompTox Dashboard (EPA)	DTXSID70152747
InChI InChI=1S/2Ga.O Key: KXACIVYKDCQNQA-UHFFFAOYSA-N
SMILES O([Ga])[Ga]
Properties
Chemical formula	Ga2O
Molar mass	155.445 g/mol[1]
Appearance	brown powder[1]
Density	4.77 g/cm3[1]
Melting point	800 °C (1,470 °F; 1,070 K)[1] (decomposes)
Magnetic susceptibility (χ)	−34·10−6 cm3/mol[2]
Thermochemistry
Std enthalpy of formation (ΔfH⦵298)	−356.2 kJ/mol[3]
Related compounds
Other cations	Boron monoxide Aluminium(I) oxide Indium(I) oxide Thallium(I) oxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Production

Gallium(I) oxide can be produced by reacting gallium(III) oxide with heated gallium in vacuum:^[4]

${\displaystyle \mathrm {Ga_{2}O_{3}+4\ Ga\longrightarrow 3\ Ga_{2}O} }$

It can also be obtained by reacting gallium with carbon dioxide in vacuum at 850 °C.^[5]

${\displaystyle \mathrm {2\ Ga+CO_{2}\longrightarrow Ga_{2}O+CO} }$

Gallium(I) oxide is a by-product in the production of gallium arsenide wafers:^[6][7]

${\displaystyle \mathrm {4\ Ga+SiO_{2}\longrightarrow 2\ Ga_{2}O+Si} }$

Properties

Gallium(I) oxide is a brown-black diamagnetic solid which is resistant to further oxidation in dry air. It starts decomposing upon heating at temperatures above 500 °C, and the decomposition rate depends on the atmosphere (vacuum, inert gas, air).^[4]