Germanium tetrabromide

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| ImageFile = File:GeBr4.png

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| IUPACName = tetrabromogermane

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| Section1 = {{Chembox Identifiers

| CASNo = 13450-92-5

| CASNo_Ref = {{Cascite|correct|CAS}}

| ChemSpiderID = 24230

| EINECS = 236-612-1

| PubChem = 26011

| StdInChI=1S/Br4Ge/c1-5(2,3)4

| StdInChIKey = VJHDVMPJLLGYBL-UHFFFAOYSA-N

| SMILES = [Ge](Br)(Br)(Br)Br

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| Section2 = {{Chembox Properties

|Ge=1|Br=4

| Formula =

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| Appearance = Colorless solid

| Density = 2.123 g/cm³

| MeltingPtC = 26

| BoilingPtC = 185.9

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| Section3 = {{Chembox Hazards

| GHSPictograms = {{GHS05}}

| GHSSignalWord = Danger

| HPhrases = {{H-phrases|314}}

| PPhrases = {{P-phrases|260|264|280|301+330+331|303+361+353|304+340|305+351+338|310|321|363|405|501}}

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| Section4 = {{Chembox Structure

| Structure_ref ={{cite journal | last1=Köhler | first1=J. | last2=Okudera | first2=Η. | last3=Simon | first3=A. | title=Crystal structure of germanium tetrabromide, β-GeBr4, low temperature modification | journal=Zeitschrift für Kristallographie - New Crystal Structures | publisher=Walter de Gruyter GmbH | volume=220 | issue=1–4 | year=2005 | issn=2197-4578 | doi=10.1524/ncrs.2005.220.14.554 | page=554|doi-access=free}}

| CrystalStruct = α-Cubic (SnI₄ type)
β-Monoclinic (SnBr₄ type)

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| Section5 = {{Chembox Thermochemistry

| DeltaHf = 83.3 kcal/mol

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| Section9 = {{Chembox Related

| OtherAnions = Germanium tetrafluoride
Germanium tetrachloride
Germanium tetraiodide

| OtherCations = Carbon tetrabromide
Silicon tetrabromide
Tin(IV) bromide

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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:{{cite book|author1=P. W. Schenk|chapter=Silicon and Germanium|title=Handbook of Preparative Inorganic Chemistry, 2nd Ed. |editor=G. Brauer|publisher=Academic Press|year=1963|place=NY, NY|volume=2page=718}}

:{{chem2|Ge + Br2 → GeBr4}}

From this reaction, GeBr₄ has a heat of formation of 83.3 kcal/mol.{{cite journal | last1=Evans | first1=D. F. | last2=Richards | first2=R. E. | title=233. The heats of formation of germanium tetrabromide and germanium tetraiodide | journal=Journal of the Chemical Society (Resumed) | publisher=Royal Society of Chemistry (RSC) | year=1952 | issn=0368-1769 | doi=10.1039/jr9520001292 | page=1292}}

The compound is liquid at 25 °C, and forms an interlocking liquid structure.{{cite journal | last1=Swamy | first1=K. N. | last2=Bhuiyan | first2=L. B. | title=The Reference Interaction Site Model and the Structure of Liquid Germanium Tetrabromide | journal=Physics and Chemistry of Liquids | publisher=Informa UK Limited | volume=9 | issue=2 | year=1980 | issn=0031-9104 | doi=10.1080/00319108008084774 | pages=169–174}} 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.