Tetrakis(methylammonium) hexachloroferrate(III) chloride
Names | |
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IUPAC name
Tetrakis(methylammonium) hexachloroferrate(III) chloride | |
Identifiers | |
3D model (JSmol) |
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Properties | |
C4H24Cl7FeN4 | |
Molar mass | 432.26 g·mol−1 |
Appearance | orange crystals |
Density | 1.58 g cm−3[1] |
Melting point | 155 °C (311 °F; 428 K) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
verify (what is ?) | |
Infobox references | |
Tetrakis(methylammonium) hexachloroferrate(III) chloride is a chemical compound with the formula (CH3NH3)4[FeCl6]Cl.
Properties
The compound has the form of orange crystals.[2] Six chloride ions are coordinated to the central iron atom leading to octahedral geometry. Interstitial chlorine ions are surrounded by the electrostatically attracted positively charged methylammonium groups.[1] The NH3 groups are bonded to the [FeCl6]3−.[1] The iron within the molecule is in the three coordinate state.
The molecular weight is 432.3 g/mol. The density of this compound is 1.58 g cm−3.[1] Crystal dimensions are 0.25 × 0.35 × 0.16 mm. The melting point is 155 °C. The [FeCl6]3− acts as a Lewis acid, while the ammonium group acts as a Lewis base. It is a hydroscopic compound.[2]
Synthesis
The compound is synthesised by reacting methylammonium chloride, CH3NH3Cl, with anhydrous iron(III) chloride and adding hydrochloric acid with heating. Crystals of the product will precipitate as the solvent evaporates; they are then collected and dried using vacuum desiccation.[2]
Infrared Analysis
There is a series of nitrogen hydrogen amine stretching from 3129 to 2830 cm−1. In addition a distinct peak is found at 2517 cm−1 which corresponds well with the peak at 2476 cm−1 for methylammonium chloride and the literature estimate of a peak present near 2500 cm−1.[1][3] The 31 cm−1 shift indicates changes in the methylammonium chloride due to coordination with chlorine in the product crystals.
Notes
- 1 2 3 4 5 James, B. D.; Bakalova, M.; Lieseganga, J.; Reiff, W. M.; Hockless, D. C. R.; Skelton, B. W.; White, A. H. (1996). "The hexachloroferrate(III) anion stabilized in hydrogen bonded packing arrangements. A comparison of the X-ray crystal structures and low temperature magnetism of tetrakis(methylammonium) hexachloroferrate(III) chloride (I) and tetrakis(hexamethylenediammonium) hexachloroferrate(III) tetrachloroferrate(III) tetrachloride (II)". Inorganica Chimica Acta. 247 (2): 169–174. doi:10.1016/0020-1693(95)04955-X.
- 1 2 3 Clausen, C. A.; Good, M. L. (1968). "Stabilization of the hexachloroferrate(III) anion by the methylammonium cation". Inorganic Chemistry. 7 (12): 2662–2663. doi:10.1021/ic50070a047.
- ↑ "methyl ammonium chloride" http://riodb01.ibase.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi