Samarium (III) fluoride
Crystal structure | ||||||||||||||||
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__ Sm 3+ __ F - | ||||||||||||||||
Crystal system | ||||||||||||||||
Space group |
Pnma (No. 62) |
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Lattice parameters |
a = 666.9 pm |
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Coordination numbers |
Sm [9], F [3] |
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General | ||||||||||||||||
Surname | Samarium (III) fluoride | |||||||||||||||
other names |
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Ratio formula | SmF 3 | |||||||||||||||
Brief description |
yellowish-white |
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External identifiers / databases | ||||||||||||||||
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properties | ||||||||||||||||
Molar mass | 207.36 g mol −1 | |||||||||||||||
Physical state |
firmly |
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Melting point |
1306 ° C |
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safety instructions | ||||||||||||||||
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As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Samarium (III) fluoride (SmF 3 ) is a salt of the rare earth metal samarium .
Extraction and presentation
Samarium (III) fluoride can be obtained by reacting samarium (III) oxide with hydrogen fluoride .
properties
At room temperature , samarium (III) fluoride assumes the orthorhombic β-YF 3 structure with the space group Pnma (space group no. 62) . The lattice constants are a = 666.9 pm , b = 705.9 pm and c = 440.5 pm. Above 495 ° C it takes on the trigonal LaF 3 structure with the space group P 3 c 1 (space group no. 165) . Here the lattice constants are a = 707 pm and c = 724 pm.
Individual evidence
- ↑ a b American Elements: Samarium Fluoride , accessed August 1, 2015.
- ↑ a b Datasheet Samarium (III) fluoride, anhydrous, powder, 99.99% from Sigma-Aldrich , accessed on September 29, 2013 ( PDF ).
- ↑ Georg Brauer (Ed.), With the collaboration of Marianne Baudler a . a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume I, Ferdinand Enke, Stuttgart 1975, ISBN 3-432-02328-6 , p. 254.
- ↑ K. Rotereau, Ph. Daniel, A. Desert, JY Gesland: The high-temperature phase transition in samarium fluoride, SmF 3 : structural and vibrational investigation. In: Journal of Physics: Condensed Matter , 1998 , 10 , pp. 1431-1446, doi : 10.1088 / 0953-8984 / 10/6/026 .