Germanium tetrabromide

Germanium tetrabromide
Names
	IUPAC name tetrabromogermane
Identifiers
CAS Number	13450-92-5 ;
3D model (JSmol)	Interactive image;
ChemSpider	24230;
ECHA InfoCard	100.033.270
EC Number	236-612-1;
PubChem CID	26011;
CompTox Dashboard (EPA)	DTXSID2065468 ;
	InChI InChI=1S/Br4Ge/c1-5(2,3)4 Key: VJHDVMPJLLGYBL-UHFFFAOYSA-N;
	SMILES [Ge](Br)(Br)(Br)Br;
Properties
Chemical formula	Br4Ge
Molar mass	392.246 g·mol−1
Appearance	Colorless solid
Density	2.123 g/cm3
Melting point	26 °C (79 °F; 299 K)
Boiling point	185.9 °C (366.6 °F; 459.0 K)
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H314
Precautionary statements	P260, P264, P280, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P363, P405, P501
Structure
Crystal structure	α-Cubic (SnI4 type); β-Monoclinic (SnBr4 type)
Thermochemistry
Std enthalpy of; formation (ΔfH⦵298)	83.3 kcal/mol
Related compounds
Other anions	Germanium tetrafluoride; Germanium tetrachloride; Germanium tetraiodide
Other cations	Carbon tetrabromide; Silicon tetrabromide; Tin(IV) bromide
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Germanium tetrabromide is the inorganic compound with the formula GeBr₄. It is a colorless solid that melts near room temperature. It can be formed by treating solid germanium with bromine, or by treating a germanium-copper mixture with bromine:^[2]

Ge + Br₂ → GeBr₄

From this reaction, GeBr₄ has a heat of formation of 83.3 kcal/mol.^[3]

The compound is liquid at 25 °C, and forms an interlocking liquid structure.^[4] From room temperature down to −60 °C the structure takes on a cubic α form, whereas at lower temperatures it takes on a monoclinic β form.

^ Köhler, J.; Okudera, Η.; Simon, A. (2005). "Crystal structure of germanium tetrabromide, β-GeBr4, low temperature modification". Zeitschrift für Kristallographie - New Crystal Structures. 220 (1–4). Walter de Gruyter GmbH: 554. doi:10.1524/ncrs.2005.220.14.554. ISSN 2197-4578.
^ P. W. Schenk (1963). "Silicon and Germanium". In G. Brauer (ed.). Handbook of Preparative Inorganic Chemistry, 2nd Ed. Vol. 2page=718. NY, NY: Academic Press.
^ Evans, D. F.; Richards, R. E. (1952). "233. The heats of formation of germanium tetrabromide and germanium tetraiodide". Journal of the Chemical Society (Resumed). Royal Society of Chemistry (RSC): 1292. doi:10.1039/jr9520001292. ISSN 0368-1769.
^ Swamy, K. N.; Bhuiyan, L. B. (1980). "The Reference Interaction Site Model and the Structure of Liquid Germanium Tetrabromide". Physics and Chemistry of Liquids. 9 (2). Informa UK Limited: 169–174. doi:10.1080/00319108008084774. ISSN 0031-9104.

[1] Köhler, J.; Okudera, Η.; Simon, A. (2005). "Crystal structure of germanium tetrabromide, β-GeBr4, low temperature modification". Zeitschrift für Kristallographie - New Crystal Structures. 220 (1–4). Walter de Gruyter GmbH: 554. doi:10.1524/ncrs.2005.220.14.554. ISSN 2197-4578.

[2] P. W. Schenk (1963). "Silicon and Germanium". In G. Brauer (ed.). Handbook of Preparative Inorganic Chemistry, 2nd Ed. Vol. 2page=718. NY, NY: Academic Press.

[3] Evans, D. F.; Richards, R. E. (1952). "233. The heats of formation of germanium tetrabromide and germanium tetraiodide". Journal of the Chemical Society (Resumed). Royal Society of Chemistry (RSC): 1292. doi:10.1039/jr9520001292. ISSN 0368-1769.

[4] Swamy, K. N.; Bhuiyan, L. B. (1980). "The Reference Interaction Site Model and the Structure of Liquid Germanium Tetrabromide". Physics and Chemistry of Liquids. 9 (2). Informa UK Limited: 169–174. doi:10.1080/00319108008084774. ISSN 0031-9104.

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