Ammonium hexafluoroarsenate

Ammonium hexafluoroarsenate is an inorganic chemical compound with the chemical formula NH₄AsF₆.

Synthesis

Arsenic pentoxide is mixed with an excess of ammonium fluoride; the mixture is fused to produce ammonium hexafluoroarsenate:

AsF₅ NH₄F → NH₄AsF₆

Also, reaction of arsenic trifluoride, hydrofluoric acid, and ammonia:

AsF₃ HF NH₄ → NH₄AsF₆

Treatment of hexafluoroarsenic acid and ammonia:

HAsF₆ NH₃ → NH₄AsF₆

Physical properties

Ammonium hexafluoroarsenate crystallizes rhombohedral with the KOsF₆ structure type, with parameters: a = 7.459(3) Å, c = 7.543(3) Å (at 200 K), Z = 3, unit cell volume 363.4 Å³, space group R3 (No. 148).

References