Silver(I,III) oxide
 Ag(I) Ag(III) O
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| IUPAC name
silver(I,III) Oxide
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Other names
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CAS Number
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3D model (JSmol)
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| ECHA InfoCard | 100.013.726 |
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PubChem CID
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InChI
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SMILES
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| Properties | |
Chemical formula
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Ag4O4 Ag2O.Ag2O3 |
| Molar mass | 123.87 g/mol |
| Appearance | grey-black powder diamagnetic |
| Density | 7.48 g/cm3 |
| Melting point | >100 °C (decomposes) |
Solubility in water
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0.0027 g/100 mL |
| Solubility | soluble in alkalis |
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Pictograms
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Signal word
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Danger |
Hazard statements
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H272, H315, H319, H335 |
| NFPA 704 (fire diamond) | 
3
0
1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references
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Silver(I,III) oxide or tetrasilver tetroxide is the inorganic compound with the formula Ag4O4. It is a component of silver zinc batteries. It can be prepared by the slow addition of a silver(I) salt to a persulfate solution e.g. AgNO3 to a Na2S2O8 solution.[1] It adopts an unusual structure, being a mixed-valence compound.[2] It is a dark brown solid that decomposes with evolution of O2 in water. It dissolves in concentrated nitric acid to give brown solutions containing the Ag2+ ion.[3]
Structure
Although its empirical formula, AgO, suggests that the compound tetrasilver tetraoxide has silver in the +2 oxidation state, each unit has two monovalent silver atoms bonded to an oxygen atom, and two trivalent silver atoms bonded to three oxygen atoms, and it is in fact diamagnetic. X-ray diffraction studies show that the silver atoms adopt two different coordination environments, one having two collinear oxide neighbours and the other four coplanar oxide neighbours.[1] tetrasilver tetraoxide is therefore formulated as AgIAgIIIO2[4] or Ag2O·Ag2O3. It has previously been called silver peroxide, which is incorrect since it does not contain the peroxide ion, O22−.
Uses
Tetrasilver tetroxide has been marketed under a trade name "Tetrasil." In 2010, the FDA issued a warning letter to an American company concerning the firm's marketing of Tetrasil and Genisil ointments of tetrasilver tetroxide for herpes and similar conditions.[5]
Notes
- ^ https://pubchem.ncbi.nlm.nih.gov/compound/44150047 lists only CAS 155645-89-9. Perhaps the CASNo 1301-96-8 is due to https://patents.justia.com/patent/6645531 (Antelman, year 2000): "Tetrasilver tetroxide compositions... have been commercially sold under the poorly named “Ag(II) OXIDE” tradename. They may be obtained from Aldrich Chemical Co., Inc..."
References
- ^ a b Wells A.F. (1984) Structural Inorganic Chemistry 5th edition Oxford Science Publications ISBN 0-19-855370-6
- ^ David Tudela "Silver(II) Oxide or Silver(I,III) Oxide?" J. Chem. Educ., 2008, volume 85, p 863. doi:10.1021/ed085p863
- ^ Peter Fischer, Martin Jansen "Electrochemical Syntheses of Binary Silver Oxides" 1995, vol. 30, pp. 50–55. doi:10.1002/9780470132616.ch11
- ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. doi:10.1016/C2009-0-30414-6. ISBN 978-0-08-037941-8. p. 1181.
- ^ "FDA Warning Letter to Aidance Skincare and Topical Solutions, LLC | Quackwatch". 19 July 2010.