Niobium (IV) iodide
Crystal structure | |||||||
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__ Nb 4+ __ I - | |||||||
General | |||||||
Surname | Niobium (IV) iodide | ||||||
other names |
Niobium tetraiodide |
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Ratio formula | NbI 4 | ||||||
Brief description |
gray solid |
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External identifiers / databases | |||||||
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properties | |||||||
Molar mass | 600.52 g mol −1 | ||||||
Physical state |
firmly |
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density |
5.6 g cm −3 |
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Melting point |
503 ° C |
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solubility |
reacts with water |
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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 . |
Niobium (IV) iodide is a chemical compound of niobium from the group of iodides .
Extraction and presentation
Niobium (IV) iodide can be obtained by decomposing niobium (V) iodide at 206 to 270 ° C in a vacuum.
properties
Niobium (IV) iodide is a gray solid that reacts with water
It has an orthorhombic crystal structure with the space group Cmc 2 1 (space group no. 36) . The structure consists of chains of edge-sharing NbI 6 octahedra, which are characterized by the formation of Nb 2 groups with an Nb – Nb bond. At temperatures above 348 and 417 ° C, the transformation to another crystal structure takes place. At very high pressures it changes into a metallic structure.
Individual evidence
- ↑ a b c d e William M. Haynes: CRC Handbook of Chemistry and Physics, 97th Edition . CRC Press, 2016, ISBN 978-1-4987-5429-3 , pp. 76 ( limited preview in Google Book search).
- ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
- ^ Dale L. Perry: Handbook of Inorganic Compounds, Second Edition . CRC Press, 2016, ISBN 978-1-4398-1462-8 , pp. 298 ( limited preview in Google Book search).
- ↑ LF Dahl, DL Wampler: The crystal structure of α-niobium tetraiodide. In: Acta Crystallographica. 15, 1962, p. 903, doi : 10.1107 / S0365110X62002340 .
- ^ Viktor Gutmann: Halogen Chemistry . Elsevier, 2012, ISBN 0-323-14847-6 , pp. 170 ( limited preview in Google Book search).
- ↑ H. Kawamura, N. Matsui, I. Nakahata, M. Kobayashi, Y. Akahama, I. Shirotani: Structural studies of NbI 4 at high pressures. In: Solid State Communications. 108, 1998, p. 919, doi : 10.1016 / S0038-1098 (98) 00483-9 .