Silver subfluoride

Silver subfluoride
IUPAC name silver(0,I) fluoride
Identifiers
CAS number	1302-01-8
Properties
Molecular formula	Ag2F
Molar mass	234.734 g/mol
Appearance	Bronze-colored crystals with green luster
Density	8.6 g/cm3, solid
Melting point	90 °C. decomposition
Y subfluoride (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Silver subfluoride is the inorganic compound with the formula Ag₂F. This is an unusual example of a compound where the oxidation state of silver is fractional. The is prepared by the reaction of silver and silver fluoride:^[1]

Ag + AgF → Ag₂F

It forms small crystals with a bronze reflex and is a good conductor of electricity. On contact with water almost instant hydrolysis occurs with the precipitation of silver (Ag) powder.

Crystal structure

Ag₂F adopts the anti-CdI₂ crystal structure, i.e. the same structure as cadmium iodide, CdI₂, but with "Ag^½+ " centres in the I⁻ positions and F⁻ in the Cd²⁺ positions.^[2] The shortest distance between silver atoms is 299.6 pm (compared to 289 pm in the metal).^[3]

References

1. ^ Lee Poyer, Maurice Fielder, Hugh Harrison, Burl E. Bryant "Disilver Fluoride: (Silver “Subfluoride”)" Inorganic Syntheses, 1957, Volume 5, 92–94. doi:10.1002/9780470132364.ch6
2. ^ A Williams (April 1989). "Neutron powder diffraction study of silver subfluoride". J. Phys.: Condens. Matter 1 (15): 2569–2574. doi:10.1088/0953-8984/1/15/002. 
3. ^ Egon Wiberg, Arnold Frederick Holleman (2001) Inorganic Chemistry, Elsevier ISBN 0-12-352651-5