Ammonium pentachloroferrate(III)

From Crystal growing

   Ammonium pentachloroferrate(III)   
Names: ammonium pentachloroferrate
diammonium pentachloroferrate
ammonium ferrichloride
Formula: (NH4)2[FeCl5(H2O)] (anhydrous)
(NH4)2[FeCl5(H2O)] · H2O (monohydrate)
Molar mass: 287.202 g/mol (anhydrous)
305.217 g/mol (monohydrate)
Crystal system: orthorhombic (monohydrate)
a=13.706 Å, b=9.924 Å, c=7.024 Åα=90°, β=90°, γ=90°

Color: red-brown
Decomposition point: 87 °C360.15 K <br />188.6 °F <br />648.27 °R <br /> (tetrahydrate)
Electricity properties: ferroelectric
Magnetic properties: antiferromagnetic
Stability: slowly erodes (monohydrate)
hygroscopic (anhydrous)
Hardness: fragile
Toxicity: slightly toxic


Inorganic complex compound, salt of ammonium ion and complex pentachloroferrate ion. From water solutions crystallizes as monohydrate.


Reaction between ammonium and iron(III) chlorides

Chemical equation:

2NH4Cl + FeCl3 + H2O = (NH4)2[FeCl5(H2O)]

For preparation of 100.00g of ammonium pentachloroferrate(III) monohydrate а 35.05g of chloride ammonium and 88.56g of chloride iron(III) hexahydrate is required.

Dissolve compounds in hot water apart and then mix solutions into one container with intense stirring. Cooling or evaporation of a solution will cause double salt crystallyzation.

Influence of temperature

Grow at room temperature. Heating of solution leads to iron(III) chloride hydrolysis.

Storage conditions

Store in its original form or under several layers of varnish at average humidity and room temperature. Do not store in matchboxes or cotton wool and do not heat.


Highly soluble in water.