Compounds
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Terbium combines with nitrogen, carbon, sulfur, phosphorus, boron, selenium, silicon and arsenic at elevated temperatures, forming various binary compounds such as TbH2, TbH3, TbB2, Tb2S3, TbSe, TbTe and TbN.[1] In those compounds, Tb mostly exhibits the oxidation states +3 and sometimes +2. Terbium(II) halides are obtained by annealing Tb(III) halides in presence of metallic Tb in tantalum containers. Terbium also forms sesquichloride Tb2Cl3, which can be further reduced to TbCl by annealing at 800 °C. This terbium(I) chloride forms platelets with layered graphite-like structure.[2]
Terbium(IV) fluoride is the only halide that tetravalent terbium can form, and has strong oxidizing properties. It is also a strong fluorinating agent, emitting relatively pure atomic fluorine when heated, rather than the mixture of fluoride vapors emitted from cobalt(III) fluoride or cerium(IV) fluoride.[3] It can be obtained by reacting terbium(III) chloride or terbium(III) fluoride with fluorine gas at 320 °C:[4]
- 2 TbF3 + F2 → 2 TbF4
When TbF4 and CsF is mixed in a stoichiometric ratio, in a fluorine gas atmosphere, CsTbF5 is obtained. It is an orthorhombic crystal, with space group Cmca, with a layered structure composed of [TbF8]4− and 11-coordinated Cs+.[5] The compound BaTbF6 can be prepared in a similar method. It is an orthorhombic crystal, with space group Cmma. The compound [TbF8]4− also exists.[6]
Other compounds include
- ^ Cite error: The named reference
patnaikwas invoked but never defined (see the help page). - ^ Cotton (2007). Advanced inorganic chemistry (6th ed.). Wiley-India. p. 1128. ISBN 978-81-265-1338-3.
- ^ Rau, J. V.; Chilingarov, N. S.; Leskiv, M. S.; Sukhoverkhov, V. F.; Rossi Albertini, V.; Sidorov, L. N. (August 2001). "Transition and rare earth metal fluorides as thermal sources of atomic and molecular fluorine". Le Journal de Physique IV. 11 (PR3): Pr3–109–Pr3-113. doi:10.1051/jp4:2001314.
- ^ Synthesis of Lanthanide and Actinide Compounds. Springer Science & Business Media. 1991. p. 60. ISBN 978-0-7923-1018-1.
{{cite book}}: Unknown parameter|authors=ignored (help) - ^ Gaumet, V.; Avignant, D. (1997). "Caesium Pentafluoroterbate, CsTbF5". Acta Crystallographica Section C: Crystal Structure Communications. 53 (9): 1176–1178. doi:10.1107/S0108270197005556.
- ^ Largeau, E.; El-Ghozzi, M.; Métin, J.; Avignant, D. (1997). "β-BaTbF6". Acta Crystallographica Section C: Crystal Structure Communications. 53 (5): 530–532. doi:10.1107/S0108270196014527.