Chemistry:Tantalum(IV) iodide

From HandWiki
Tantalum(IV) iodide
TaI4.png
Identifiers
3D model (JSmol)
Properties
TaI4
Molar mass 688.57
Appearance black solid[1]
Melting point 398 °C (671 K) (decomposes)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Tantalum(IV) iodide is an inorganic compound with the chemical formula TaI4. It dissolves in water to give a green solution, but the color fades when left in the air and produces a white precipitate.[2]

Preparation

Tantalum(IV) iodide can be prepared by the reduction reaction of tantalum(V) iodide and tantalum.[2] If pyridine is used as the reducing agent, there is an adduct TaI4(py)2.[3]

Tantalum(IV) iodide can also be obtained by reacting tantalum(V) iodide with aluminum, magnesium or calcium at 380 °C. Ta6I14 is also formed. This makes it difficult to produce a very pure crystallized tantalum(IV) iodide.[4]

3 TaI
5
+ Al → 3 TaI
4
+ AlI
3

Properties

Tantalum(IV) iodide is a black solid. It has a crystal structure isotypic to that of niobium(IV) iodide.[4] Single-crystalline tantalum(IV) iodide was first obtained in 2008 by Rafal Wiglusz and Gerd Meyer as a chance product of a reaction in a tantalum ampoule that was supposed to lead to the product Rb(Pr6C2)I12.[5] The single crystal has a triclinic crystal structure with space group P1 (space group no. 2) with two formula units per unit cell (a = 707.36 pm, b = 1064.64 pm, c = 1074.99 pm, α = 100.440°, β = 89.824° and γ = 104.392°). The crystal structure differs from that of other transition metal tetraiodides, which usually have a MI4/2I2/1 chain structure, as it consists of TaI6 octahedra bridged over a common surface to form a dimer. Two such dimers bridge over a common edge to form a tetramer.[6]

References

  1. Georg Brauer: Handbuch der präparativen anorganischen Chemie. 3., umgearb. Auflage. Band III. Enke, Stuttgart 1981, ISBN 3-432-87823-0, pp. 1455.
  2. 2.0 2.1 Robert F. Rolsten (Jun 1958). "Preparation and X-ray Study of Some Tantalum Halides" (in en). Journal of the American Chemical Society 80 (12): 2952–2953. doi:10.1021/ja01545a011. ISSN 0002-7863. https://pubs.acs.org/doi/abs/10.1021/ja01545a011. Retrieved 2021-03-24. 
  3. R. E. McCarley, J. C. Boatman (Jun 1963). "The Preparation of Tantalum(IV) Bromide, Tantalum(IV) Iodide, and Pyridine Adducts of the Tantalum(IV) Halides" (in en). Inorganic Chemistry 2 (3): 547–551. doi:10.1021/ic50007a030. ISSN 0020-1669. https://pubs.acs.org/doi/abs/10.1021/ic50007a030. Retrieved 2021-03-24. 
  4. 4.0 4.1 Handbuch der präparativen anorganischen Chemie. 3 (3., umgearb. Aufl ed.). Stuttgart: Enke. 1981. ISBN 978-3-432-87823-2. 
  5. Meyer, Gerd; Wiglusz, Rafal; Pantenburg, Ingo; Mudring, Anja-Verena (May 2008). "Tantalum(IV) Iodide, TaI4: A Molecular Solid Consisting of Dimers of Dimers, Ta4I16" (in de). Zeitschrift für anorganische und allgemeine Chemie 634 (5): 825–828. doi:10.1002/zaac.200700529. https://onlinelibrary.wiley.com/doi/10.1002/zaac.200700529. 
  6. Habermehl, Katja (2010). Neue Untersuchungen an Halogeniden des Niobs und Tantals (text.thesis.doctoral thesis). Universität zu Köln.
HI He
LiI BeI2 BI3 CI4 NI3 I2O4,
I2O5,
I4O9
IF,
IF3,
IF5,
IF7
Ne
NaI MgI2 AlI3 SiI4 PI3,
P2I4
S ICl,
ICl3
Ar
KI CaI2 Sc TiI4 VI3 CrI3 MnI2 FeI2 CoI2 NiI2 CuI ZnI2 Ga2I6 GeI2,
GeI4
AsI3 Se IBr Kr
RbI SrI2 YI3 ZrI4 NbI5 Mo Tc Ru Rh Pd AgI CdI2 InI3 SnI4,
SnI2
SbI3 TeI4 I Xe
CsI BaI2   HfI4 TaI5 W Re Os Ir Pt AuI Hg2I2,
HgI2
TlI PbI2 BiI3 Po AtI Rn
Fr RaI2   Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
La Ce Pr Nd Pm SmI2 Eu Gd TbI3 Dy Ho Er Tm Yb Lu
Ac ThI4 Pa UI3,
UI4
Np Pu Am Cm Bk Cf EsI3 Fm Md No Lr