Gold chalcogenides are compounds formed between
gold
Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile ...
and one of the
chalcogens, elements from
group 16 of the
periodic table:
oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements ...
,
sulfur,
selenium, or
tellurium.
*
Gold(III) oxide, Au
2O
3. Decomposes into gold and oxygen above 160 °C, and dissolves in concentrated alkalis to form solutions which probably contain the
u(OH)4sup>− ion
*
Gold(I) sulfide, Au
2S. Formed by passing
hydrogen sulfide through solutions of gold(I) compounds.
*
Gold(III) sulfide, Au
2S
3, unstable in the presence of water.
*Gold tellurides: Au
2Te
3, Au
3Te
5, and AuTe
2 (approximate formulæ) are known as
non-stoichiometric compounds. They show
metallic conductivity. One telluride of gold is a
superconductor at very low temperatures: Au
3Te
5 (1.62 K).
Natural gold tellurides, like
calaverite and
krennerite (AuTe
2),
petzite ( Ag
3AuTe
2), and
sylvanite (AgAuTe
4), are minor ores of gold (and tellurium). See
telluride minerals for more information on individual naturally occurring tellurides.
References
*
Gold compounds
Non-stoichiometric compounds
Sulfides
Tellurides
{{inorganic-compound-stub
Transition metal oxides