Tellurium (I) iodide

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Crystal structure
Crystal structure of tellurium (I) iodide
__ Te +      __ I -
General
Surname Tellurium (I) iodide
other names
  • Tellurium monoiodide
  • Tetratellurtetraiodide
Ratio formula Part
Brief description

black solid

External identifiers / databases
CAS number
  • 12600-42-9
  • 51380-73-5
Wikidata Q7697690
properties
Molar mass 254.50 g mol −1
Physical state

firmly

density

5.51 g cm −3

Melting point

185 ° C

safety instructions
GHS hazard labeling
no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Tellurium (I) iodide is a chemical compound from the group of iodides .

Extraction and presentation

Tellurium (I) iodide can be obtained by reacting tellurium with iodine . This synthesis was first carried out in 1973 by Rüdiger Kniep . The synthesis can also be represented by reaction of tellurium with concentrated hydriodic acid or by reaction of tellurium with tellurium tetraiodide in an ionic liquid .

properties

Tellurium (I) iodide is a black solid that occurs in two crystal structures . α-TeI crystallizes triclinically with the space group P 1 (space group no.2 ) , z = 8, with lattice constants a = 9.958 (3), b = 7.992 (2), c = 8.212 (4) Å, α = 104, 37 (11), β = 90.13 (4) and γ = 102.89 (7) °. The macromolecular structure of the subhalides of tellurium has degenerated into a Te 4 ring (the Te 4 I 4 molecule) in the α part . β-TeI crystallizes monoclinically with the space group C 2 / m (space group no.12 ) , z = 8, with lattice constants a = 15.383 (2), b = 4.182 (2), c = 11.999 (2) Å and β = 128.09 (1) °. The structure consists of infinite chains of tellurium atoms, on which the iodine atoms alternately occupy bridging and terminal positions. Template: room group / 2 Template: room group / 12

Phase studies in the Te-TeI 4 system show that the compound is the only thermodynamically stable phase of the pseudo-binary system. The phase width of Te x I assumed earlier is a further stoichiometrically composed 1: 1 phase mixed with Te 2 I. The compound that is stable with respect to the phase diagram is called α-TeI, the compounds β-TeI and Te 2 I have a metastable character.

Individual evidence

  1. ^ A b c Carl L. Yaws: The Yaws Handbook of Physical Properties for Hydrocarbons and Chemicals Physical Properties for More Than 54,000 Organic and Inorganic Chemical Compounds, Coverage for C1 to C100 Organics and Ac to Zr Inorganics . Gulf Professional Publishing, 2015, ISBN 978-0-12-801146-1 , pp. 802 ( limited preview in Google Book Search).
  2. ^ A b Matthias F. Groh, Ulrike Müller, Ejaz Ahmed, Alexander Rothenberger, Michael Ruck: Substitution of Conventional High-temperature Syntheses of Inorganic Compounds by Near-room-temperature Syntheses in Ionic Liquids. In: Zeitschrift für Naturforschung B. 68, 2013, doi : 10.5560 / ZNB.2013-3141 .
  3. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
  4. ↑ a b G. L. Cai, SX Liu, JL Huang: High-temperature synthesis and structure redetermination of Te4I4. In: Acta Crystallographica Section C Crystal Structure Communications. 47, p. 2642, doi : 10.1107 / S0108270191005656 .
  5. ↑ R. Kniep, D. Mootz, A. Rabenau: On the knowledge of the subhalides of tellurium. In: Journal of Inorganic and General Chemistry. 422, 1976, p. 17, doi : 10.1002 / zaac.19764220103 .
  6. ↑ Angew. Chem. 1 86th year 1974 1 No. 1, Rüdiger Kniep, Subhalogenide des tellurs, 1974, [1]