Gold(III) phosphate

Gold(III) phosphate

Names
Other names Auric phosphate
Identifiers
CAS Number	1204296-55-8 ^Y
3D model (JSmol)	Interactive image
PubChem CID	25254913
InChI InChI=1S/Au.H3O4P/c;1-5(2,3)4/h;(H3,1,2,3,4)/q+3;/p-3
SMILES [O-]P(=O)([O-])[O-].[Au+3]
Properties
Chemical formula	AuPO4
Molar mass	291.94 g/mol
Appearance	Pale yellow solid
Density	5.74 g/cm^3
Melting point	450 °C (842 °F; 723 K) (decomposes)
Solubility in water	Insoluble
Solubility	Insoluble in acetone
Structure
Crystal structure	Monoclinic
Coordination geometry	4 (Au)
Molecular shape	Square planar (around Au)
Thermochemistry
Std enthalpy of formation (ΔfH^⦵298)	-169.8 kJ/mol (predicted)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Gold(III) phosphate is a chemical compound with the formula AuPO₄. It is a pale yellow solid that is insoluble in water and acetone. It decomposes at 450 °C into gold metal, phosphorus pentoxide, and oxygen.^[1]

Production

Gold(III) phosphate is produced by the reaction of gold(III) hydroxide and phosphoric acid at 130 °C:^[1]

AuO(OH) + H₃PO₄ → AuPO₄ + 2H₂O

It can also be produced by the replacement of phosphoric acid with a mixture of nitric acid and phosphorus pentoxide.

References

1. "Pd₂P₂O₇ AND AuPO₄ - NEW ANHYDROUS PHOSPHATES OF NOBLE METALS". Phosphorus Research Bulletin. 19. Japanese Association of Inorganic Phosphorus Chemistry: 77–82. 2005. doi:10.3363/prb1992.19.0_77.