plutonium tetrafluoride
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| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 477171798
{{Citation | last = Lide
| first = David R.
| year = 1998 | title = Handbook of Chemistry and Physics
| edition = 87 | location = Boca Raton, Florida | publisher = CRC Press | isbn = 0-8493-0594-2 | pages = 4–76}}
| ImageFile = Plutonium_Tetrafluoride_PuF4_from_Hanford_Site_(cropped).jpg
| ImageCaption = A sample of plutonium tetrafluoride produced at the Hanford Site during the Cold War{{Cite web |url=https://osf.io/5md4c/|title=FOI 2019-00371.Loaded powder pan at RMC line|last=Pfeiffer|first=Martin|date=March 3, 2019|website=Pfeiffer Nuclear Weapon and National Security Archive|access-date=May 23, 2019}}{{Cite book |url=https://www.energy.gov/sites/prod/files/2014/03/f8/Linking_Legacies.pdf|title=Linking Legacies: Connecting the Cold War Nuclear Weapons Production Processes to Their Environmental Consequences |author=United States Department of Energy |publisher=United States Department of Energy|year=1997|location=Washington D.C.|pages=184; passim}}
| ImageFile1 = Kristallstruktur Uran(IV)-fluorid.png
| IUPACName = Plutonium(IV) fluoride
| OtherNames = Plutonium tetrafluoride
|Section1={{Chembox Identifiers
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| CASNo = 13709-56-3
| PubChem = 139558
| ChemSpiderID =123078
| StdInChI=1S/4FH.Pu/h4*1H;/q;;;;+4/p-4
| StdInChIKey = USCBBUFEOOSGAJ-UHFFFAOYSA-J
| SMILES = F[Pu](F)(F)F
}}
|Section2={{Chembox Properties
| Formula = PuF4
| MolarMass = 320 g/mol
| Appearance = reddish-brown monoclinic crystals
| Density = 7.1 g/cm3
| MeltingPtC = 1027
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|Section3={{Chembox Structure
| CrystalStruct = Monoclinic, mS60
| SpaceGroup = C12/c1, No. 15
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|Section7={{Chembox Hazards
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Plutonium(IV) fluoride is a chemical compound with the formula PuF4. This salt is generally a brown solid but can appear a variety of colors depending on the grain size, purity, moisture content, lighting, and presence of contaminants. Its primary use in the United States has been as an intermediary product in the production of plutonium metal for nuclear weapons usage.
Formation
Plutonium(IV) fluoride is produced in the reaction between plutonium dioxide (PuO2) or plutonium(III) fluoride (PuF3) with hydrofluoric acid (HF) in a stream of oxygen (O2) at 450 to 600 °C. The main purpose of the oxygen stream is to avoid reduction of the product by hydrogen gas, small amounts of which are often found in HF.Gmelins Handbuch der anorganischen Chemie, System Nr. 71, Transurane, Teil C, pp. 104–107.
:PuO2 + O2 + 4 HF → PuF4 + O2 + 2 H2O
:4 PuF3 + O2 + 4 HF → 4 PuF4 + 2 H2O
Laser irradiation of plutonium hexafluoride (PuF6) at wavelengths under 520 nm causes it to decompose into plutonium pentafluoride (PuF5) and fluorine; if this is continued, plutonium(IV) fluoride is obtained.{{Cite patent|number=4670239|title=Photochemical preparation of plutonium pentafluoride|gdate=1987-06-02|invent1=Rabideau|invent2=Campbell|inventor1-first=Sherman W.|inventor2-first=George M.|url=https://www.freepatentsonline.com/4670239.html}}
Properties
In terms of its structure, solid plutonium(IV) fluoride features 8-coordinate Pu centers interconnected by doubly bridging fluoride ligands.{{Greenwood&Earnshaw2nd}}
Reaction of plutonium tetrafluoride with barium, calcium, or lithium at 1200 °C give Pu metal:{{cite book |last1=Baldwin |first1=Charles E. |chapter=Plutonium Process Chemistry at Rocky Flats |date=1983-05-19 |title=Plutonium Chemistry |series=ACS Symposium Series |volume=216 |pages=369–380 |editor-last=Carnall |editor-first=William T. |publisher=AMERICAN CHEMICAL SOCIETY |language=en |doi=10.1021/bk-1983-0216.ch024 |isbn=9780841207721 |last2=Navratil |first2=James D. |editor2-last=Choppin |editor2-first=Gregory R.}}{{cite book |last1=Christensen |first1=Eldon L. |chapter=Present Status and Future Directions of Plutonium Process Chemistry |date=1983-05-19 |title=Plutonium Chemistry |series=ACS Symposium Series |volume=216 |pages=349–368 |editor-last=Carnall |editor-first=William T. |publisher=AMERICAN CHEMICAL SOCIETY |language=en |doi=10.1021/bk-1983-0216.ch023 |isbn=9780841207721 |last2=Grey |first2=Leonard W. |last3=Navratil |first3=James D. |last4=Schulz |first4=Wallace W. |osti=6781635 |editor2-last=Choppin |editor2-first=Gregory R.}}
:PuF4 + 2 Ba → 2 BaF2 + Pu
:PuF4 + 2 Ca → 2 CaF2 + Pu
:PuF4 + 4 Li → 4 LiF + Pu
References
{{reflist}}
{{Plutonium compounds}}
{{fluorides}}
{{Actinide halides}}