Terbium (III, IV) oxide
General | ||||||||||||||||
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Surname | Terbium (III, IV) oxide | |||||||||||||||
other names |
Tetraterbium heptoxide |
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Molecular formula | Tb 4 O 7 | |||||||||||||||
Brief description |
dark brown solid |
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properties | ||||||||||||||||
Molar mass | 747.70 g mol −1 | |||||||||||||||
Physical state |
firmly |
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density |
7.3 g cm −3 (25 ° C) |
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Melting point |
2340 ° 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 . |
Terbium (III, IV) oxide is an inorganic chemical compound of terbium from the group of oxides .
Extraction and presentation
Terbium (III, IV) oxide can be obtained by burning terbium in air. It can also be obtained from the decomposition of terbium oxalate at 600 to 1000 ° C or other terbium oxo salts in air.
properties
Terbium (III, IV) oxide is a dark brown solid. The compound is non-stoichiometric and consists of two phases with the empirical formula TbO 1.71 (Tb 7 O 12 ) and TbO 1.81 (Tb 11 O 20 ). Tb 7 O 12 has a rhombohedral crystal structure with the space group R 3 (space group no.148 ) and the lattice parameters a = 6.5082 (3) and α = 99.3420 (1), a unit cell volume of 263.32 (3) and one formula unit per unit cell. This is isomorphic with praseodymium (III, IV) oxide (Pr 7 O 12 ). Tb 11 O 20 has a triclinic crystal structure with the space group P 1 (No. 2) and the lattice parameters a = 6.50992 (4), b = 9.8298 (6), c = 6.4878 (4), α = 90.019 (2), β = 99.966 (1), γ = 95.881 (1) a unit cell volume of 406.68 (7) and also one formula unit per unit cell. Tb 4 O 7 is said to have a cubic crystal structure with the space group Fm 3 m (no. 225) .
use
Terbium (III, IV) oxide is used in fluorescent lamps and color television tubes.
Individual evidence
- ↑ a b c d e data sheet Terbium (III, IV) oxide, 99.999% trace metals basis from Sigma-Aldrich , accessed on January 11, 2015 ( PDF ).
- ↑ Data sheet Terbium (III, IV) oxide, REacton®, 99.998% (REO) from AlfaAesar, accessed on January 11, 2015 ( PDF )(JavaScript required) .
- ↑ G. Meyer, Lester R. Morss: Synthesis of Lanthanide and Actinide Compounds . Springer Science & Business Media, 1991, ISBN 0-7923-1018-7 , pp. 212 ( limited preview in Google Book search).
- ↑ KA Gschneidner, L. Eyring, MB Maple: Handbook on the Physics and Chemistry of Rare Earths: High Temperature Superconductors Rare Earths - I . Elsevier, 2000, ISBN 0-08-054437-1 , pp. 240 ( limited preview in Google Book search).
- ^ Jacques Lucas, Pierre Lucas, Thierry Le Mercier, Alain Rollat, William G. Davenport: Rare Earths: Science, Technology, Production and Use . Elsevier, 2014, ISBN 978-0-444-62744-5 , pp. 50 ( limited preview in Google Book search).
- ^ Catherine E. Housecroft, AG Sharpe: Inorganic Chemistry . Pearson Education, 2005, ISBN 0-13-039913-2 , pp. 749 ( limited preview in Google Book search).
- ^ J. Zhang, RB Von Dreele, L. Eyring: The Structures of Tb7O12 and Tb11O20 . In: Journal of Solid State Chemistry . tape 104 , no. 1 , May 1993, pp. 21-32 , doi : 10.1006 / jssc.1993.1138 .
- ↑ Rudy JM Konings, Ondrej Beneš, Attila Kovács, Dario Manara, David Sedmidubský, Lev Gorokhov, Vladimir S. Iorish, Vladimir Yungman, E. Shenyavskaya, E. Osina: The Thermodynamic Properties of the f-Elements and their Compounds. Part 2. The Lanthanide and Actinide Oxides . In: Journal of Physical and Chemical Reference Data . tape 43 , no. 1 , March 2014, p. 013101 , doi : 10.1063 / 1.4825256 .
- ↑ Pedro Oliveira: The Elements . S. 921 ( limited preview in Google Book search).