Germanium tetrafluoride

Germanium tetrafluoride (GeF₄) is a chemical compound of germanium and fluorine. It is a colorless gas.

Germanium tetrafluoride

Names
IUPAC names Germanium tetrafluoride Tetrafluorogermane Tetrafluoridogermanium
Other names Germanium(IV) fluoride Germanium fluoride
Identifiers
CAS Number	7783-58-6 Y
3D model (JSmol)	Interactive image
ChemSpider	74195 Y
ECHA InfoCard	100.029.101
EC Number	232-011-3
PubChem CID	82215
UNII	X83T8V2NRK Y
CompTox Dashboard (EPA)	DTXSID1064829
InChI InChI=1S/F4Ge/c1-5(2,3)4 Y Key: PPMWWXLUCOODDK-UHFFFAOYSA-N Y
SMILES F[Ge](F)(F)F
Properties[1]
Chemical formula	GeF4
Molar mass	148.634 g/mol
Appearance	colourless gas
Density	6.074 g/L (gas), 2.46 g/mL (liquid)[2]
Melting point	−15 °C (5 °F; 258 K) at 4 bar
Boiling point	−36.5 °C (−33.7 °F; 236.7 K) sublimates
Magnetic susceptibility (χ)	−50.0·10−6 cm3/mol
Structure
Molecular shape	tetrahedral
Thermochemistry
Std enthalpy of formation (ΔfH⦵298)	−8.008 kJ/g
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	Reacts with water to form HF, corrosive
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H314, H331, H372
Precautionary statements	P260, P261, P264, P270, P271, P280, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P311, P314, P321, P363, P403+P233, P405, P410+P403, P501
NFPA 704 (fire diamond)	3 0 2 W
Flash point	Non-flammable
Related compounds
Other anions	Germanium tetrachloride Germanium tetrabromide Germanium tetraiodide
Other cations	Carbon tetrafluoride Silicon tetrafluoride Tin tetrafluoride Lead tetrafluoride
Related compounds	Germanium difluoride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Synthesis

Germanium tetrafluoride is formed by treating germanium with fluorine:

Ge + 2 F₂ → GeF₄

Alternatively germanium dioxide combines with hydrofluoric acid (HF):^[3]

GeO₂ + 4 HF → GeF₄ + 2 H₂O

It is also formed during the thermal decomposition of a complex salt, Ba[GeF₆]:^[4]

Ba(GeF₆) → GeF₄ + BaF₂

Properties

Germanium tetrafluoride is a noncombustible, strongly fuming gas with a garlic-like odor. It reacts with water to form hydrofluoric acid and germanium dioxide. Decomposition occurs above 1000 °C.^[5]

Reaction of GeF₄ with fluoride sources produces GeF₅⁻ anions with octahedral coordination around Ge atom due to polymerization.^[6] The structural characterization of a discrete trigonal bipyramidal GeF₅⁻ anion was achieved by a "naked" fluoride reagent 1,3-bis(2,6-diisopropylphenyl)imidazolium fluoride.^[7]

Uses

In combination with disilane, germanium tetrafluoride is used for in the synthesis of SiGe.^[2]