Manganese(III) fluoride
| Names | |
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| IUPAC name
Manganese(III) fluoride
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| Other names
Manganese trifluoride, manganic fluoride
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| Identifiers | |
3D model (JSmol)
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| ChemSpider | |
| ECHA InfoCard | 100.029.096 |
| EC Number |
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PubChem CID
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| UNII | |
CompTox Dashboard (EPA)
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| Properties | |
| MnF3 | |
| Molar mass | 111.938 g/mol |
| Appearance | purple-pink powder hygroscopic |
| Density | 3.54 g/cm3 |
| Melting point | > 600 °C (1,112 °F; 873 K) (decomposes) |
| hydrolysis | |
| +10,500·10−6 cm3/mol | |
| Structure | |
| Monoclinic, mS48 | |
| C2/c, No. 15 | |
| distorted octahedral | |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards
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toxic fumes |
| GHS labelling:[1] | |
| Danger | |
| H272, H301, H312, H315, H319, H332, H335 | |
| P220, P261, P280, P301+P310, P305+P351+P338 | |
| Related compounds | |
Other anions
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manganese(III) oxide, manganese(III) acetate |
Other cations
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chromium(III) fluoride, iron(III) fluoride. cobalt(III) fluoride |
Related compounds
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manganese(II) fluoride, manganese(IV) fluoride |
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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Manganese(III) fluoride (also known as Manganese trifluoride) is the inorganic compound with the formula MnF3. This red/purplish solid is useful for converting hydrocarbons into fluorocarbons, i.e., it is a fluorination agent.[2] It forms a hydrate and many derivatives.
Synthesis, structure and reactions
MnF3 can be prepared by treating a solution of MnF2 in hydrogen fluoride with fluorine:[3]
- MnF2 + 0.5 F2 → MnF3
It can also be prepared by the reaction of elemental fluorine with a manganese(II) halide at ~250 °C.[4]
Structure
Like vanadium(III) fluoride, MnF3 features octahedral metal centers with the same average M-F bond distances. In the Mn compound, however, is distorted (and hence a monoclinic unit cell vs. a higher symmetry one) due to the Jahn-Teller effect, with pairs of Mn-F distances of 1.79, 1.91, 2.09 Å.[5][6][7]
The hydrate MnF3.3H2O is obtained by crystallisation of MnF3 from hydrofluoric acid. The hydrate exists as two polymorphs, with space groups P21/c and P21/a. Each consists of the salt [Mn(H2O)4F2]+[Mn(H2O)2F4]− ).[8]
Reactions
MnF3 is Lewis acidic and forms a variety of derivatives. One example is K2MnF3(SO4).[9] MnF3 reacts with sodium fluoride to give the octahedral hexafluoride:[4]
- 3NaF + MnF3 → Na3MnF6
Related reactions salts of the anions MnF52− or MnF4−. These anions adopt chain and layer structures respectively, with bridging fluoride. Manganese remains 6 coordinate, octahedral, and trivalent in all of these materials.[4]
Manganese(III) fluoride fluorinates organic compounds including aromatic hydrocarbons,[10] cyclobutenes,[11] and fullerenes.[12]
On heating, MnF3 decomposes to manganese(II) fluoride.[13][14]
MnF3 is a source of MnCl3 complexes by reaction with bismuth trichloride.[15]
See also
- CoF3, another fluorinating agent based on a transition metal in an oxidising +3 state.
References
- ^ GHS: sigma-aldrich 339296
- ^ Burley, G. A.; Taylor, R. (2004). "Manganese(III) Fluoride". Encyclopedia of Reagents for Organic Synthesis. J. Wiley & Sons. doi:10.1002/047084289X.rn00411. ISBN 0-471-93623-5.
- ^ Z. Mazej (2002). "Room temperature syntheses of MnF3, MnF4 and hexafluoromanganete(IV) salts of alkali cations". Journal of Fluorine Chemistry. 114 (1): 75–80. doi:10.1016/S0022-1139(01)00566-8.
- ^ a b c Inorganic chemistry, Catherine E. Housecroft, A.G. Sharpe, pp.711-712, section Manganese (III), googlebooks link
- ^ Wells, A.F. (1984) Structural Inorganic Chemistry, Oxford: Clarendon Press. ISBN 0-19-855370-6.
- ^ Hepworth, M. A.; Jack, K. H.; Nyholm, R. S. (1957). "Interatomic Bonding in Manganese Trifluoride". Nature. 179 (4552): 211–212. Bibcode:1957Natur.179..211H. doi:10.1038/179211b0. S2CID 4208409.
- ^ M. A. Hepworth; K. H. Jack (1957). "The Crystal Structure of Manganese Trifluoride, MnF3". Acta Crystallographica. 10 (5): 345–351. doi:10.1107/S0365110X57001024.
- ^ Molinier Michel; Massa Werner (1992). "Structures of two polymorphs of MnF3·3H2O". Journal of Fluorine Chemistry. 57 (1–3): 139–146. doi:10.1016/S0022-1139(00)82825-0.
- ^ Bhattacharjee, M. N; Chaudhuri, M. K. (2007). "Dipotassium Trifluorosulfato-Manganate(III)". Inorganic Syntheses. Vol. 27. pp. 312–313. doi:10.1002/9780470132586.ch61. ISBN 978-0-470-13258-6.
{{cite book}}:|journal=ignored (help) - ^ Fluorination of p-chlorobenzotrifluoride by manganese trifluoride Archived 2011-08-23 at the Wayback Machine A. Kachanov, V. Kornilov, V.Belogay, Fluorine Notes :Vol. 1 (1) November–December 1998, via notes.fluorine1.ru
- ^ Junji Mizukado; Yasuhisa Matsukawa; Heng-dao Quan; Masanori Tamura; Akira Sekiya (2006). "Fluorination of Fluoro-Cyclobutene with High-Valency Metal Fluoride". Journal of Fluorine Chemistry. 127: 79–84. doi:10.1016/j.jfluchem.2005.10.007.
- ^ V. É. Aleshina; A. Ya. Borshchevskii; E. V. Skokan; I. V. Arkhangel'skii; A.V. Astakhov; N.B. Shustova (2002). "Fluorination of the Cubic and Hexagonal C60 Modifications by Crystalline Manganese Trifluoride". Physics of the Solid State. 44 (4): 629–630. Bibcode:2002PhSS...44..629A. doi:10.1134/1.1470543. S2CID 94250136.
- ^ Chisholm, Hugh, ed. (1911). . Encyclopædia Britannica. Vol. 17 (11th ed.). Cambridge University Press. p. 570.
- ^ In situ time-resolved X-ray diffraction study of manganese trifluoride thermal decomposition, J.V. Raua, V. Rossi Albertinib, N.S. Chilingarova, S. Colonnab, U. Anselmi Tamburini, Journal of Fluorine Chemistry 4506 (2001) 1–4, online version Archived 2017-12-30 at the Wayback Machine
- ^ Nachtigall, Olaf; Pataki, Astrid; Molski, Matthias; Lentz, Dieter; Spandl, Johann (2015). "Solvates of Manganese Trichloride Revisited - Synthesis, Isolation, and Crystal Structure of MnCl3(THF)3". Zeitschrift für Anorganische und Allgemeine Chemie. 641 (6): 1164–1168. doi:10.1002/zaac.201500106.
Further reading
- Novel syntheses of some binary fluorides: the role of anhydrous hydrogen fluoride Archived 2011-08-07 at the Wayback Machine Acta Chim. Slov. 1999, 46(2), pp. 229–238, Zoran Mazej, Karel Lutar and Boris Žemva
- Knudsen Cell mass spectrometry study of Manganese Trifluoride vaporisation, High temperature corrosion and materials chemistry IV: proceedings of the International Symposium, pp. 521–525, google books