Germanium dichloride explained

Germanium dichloride is a chemical compound of germanium and chlorine with the formula . It is a yellow solid. Germanium dichloride is an example of a compound featuring germanium in the +2 oxidation state.

Preparation

Solid germanium dichloride can be produced by comproportionation by passing germanium tetrachloride,, over germanium metal at 300 °C and reduced pressure (0.1 mmHg).

Germanium dichloride is also formed from the decomposition of trichlorogermane,, at 70 °C. Trichlorogermane is generated when germanium reacts with hydrogen chloride. This reaction involves dehydrohalogenation.

Another route to germanium dichloride is the reduction of germanium tetrachloride with hydrogen at 800 °C.

Reactions

is hydrolysed to give yellow germanium(II) hydroxide, which on warming gives brown germanium monoxide:

Alkalizing a solution containing germanium(II) ions:

Germanium oxides and hydroxides are amphoteric.Solutions of in HCl are strongly reducing.[1] With chloride ion, ionic compounds containing the pyramidal ion have been characterised, for example [2] With rubidium and caesium chloride compounds, e.g. are produced; these have distorted perovskite structures.

Germanium dichloride reacts with tetraethylammonium chloride to give the trichlorogermanate:[3]

Dichlorogermylene

Molecular is often called dichlorogermylene, highlighting its resemblance to a carbene. The structure of gas-phase molecular shows that it is a bent molecule, as predicted by VSEPR theory.[4] The dioxane complex,, has been used as a source of molecular for reaction syntheses, as has the in situ reaction of and Ge metal. is quite reactive and inserts into many types of chemical bonds.[5] Usually, germanium dichloride is generated from germanium dichloride dioxane.

Notes and References

  1. Egon Wiberg, Arnold Frederick Holleman (2001) Inorganic Chemistry, Elsevier
  2. Trimethylphosphonium trichlorogermanate(II) . G. . Kociok-Köhn . Winter, J. G. . Filippou, A. C. . Acta Crystallogr. C . 1999 . 55 . 351 - 353 . 10.1107/S010827019801169X . 3.
  3. 10.1002/9780470132463.ch48. Tetraethylammonium Trichlorogermanate(l-) and Trichlorostannate(l-) . Inorganic Syntheses . 1974 . Parshall . G. W. . 15. 222–225 . 9780470132463 .
  4. Millimeter-wave spectrum of germanium dichloride GeCl2. Equilibrium structure and anharmonic force field . Honjou . Hiroaki . Tanaka. Keiichi. Tanaka. Takehiko . Tsuchiya . Masaki J. . Journal of Molecular Structure . 352 - 353 . 1995 . 407 - 415 . 10.1016/0022-2860(95)08830-O. 1995JMoSt.352..407T .
  5. Book: Egorov, M.P. . Gaspar, P. . 1994 . Germanium: Organometallic chemistry . Encyclopedia of Inorganic chemistry . John Wiley & Sons . 0-471-93620-0.