Thorium(IV) fluoride
{{chembox
| verifiedrevid = 377858902
| Name = Thorium(IV) fluoride
| ImageFile = Kristallstruktur Uran(IV)-fluorid.png
| ImageName = Thorium(IV) fluoride
Thorium tetrafluoride
| OtherNames =
|Section1={{Chembox Identifiers
| CASNo = 13709-59-6
| PubChem = 83680
| EINECS = 237-259-6
| InChI = 1S/4FH.Th/h4*1H;/q;;;;+4/p-4
| SMILES = F[Th](F)(F)F
}}
|Section2={{Chembox Properties
| Formula = ThF4
| MolarMass = 308.03 g/mol
| Appearance =white crystals
| Density = 6.3 g/cm3
| MeltingPtC = 1110
| BoilingPtC = 1680
| RefractIndex = 1.56
}}
|Section3={{Chembox Structure
| CrystalStruct = Monoclinic, mS60
| SpaceGroup = C12/c1, No. 15
}}
|Section7={{Chembox Hazards
| FlashPt = Non-flammable
}}
|Section8={{Chembox Related
| OtherAnions = Thorium(IV) chloride
Thorium(IV) bromide
Thorium(IV) iodide
| OtherCations = Protactinium(IV) fluoride
Uranium(IV) fluoride
Neptunium(IV) fluoride
Plutonium(IV) fluoride
| OtherCompounds = Thorium dioxide
}}
}}
Thorium(IV) fluoride (ThF4) is an inorganic chemical compound. It is a white hygroscopic powder which can be produced by reacting thorium with fluorine gas. At temperatures above 500 °C, it reacts with atmospheric moisture to produce ThOF2.{{cite book|url=https://books.google.com/books?id=0fT4wfhF1AsC&pg=PA412|page=412|title=Handbook of inorganic compounds|author=Dale L. Perry, Sidney L. Phillips|publisher=CRC Press|year=1995|isbn=0-8493-8671-3}}
Uses
Despite its (mild) radioactivity, thorium fluoride is used as an antireflection material in multilayered optical coatings. It has excellent optical transparency in the range 0.35–12 μm, and its radiation is primarily due to alpha particles, which can be easily stopped by a thin cover layer of another material.{{cite book|url=https://books.google.com/books?id=_VsEiRoFnXcC&pg=PA196|page=196|title=Optical thin films: user handbook|author=James D. Rancourt|publisher=SPIE Press|year=1996|isbn=0-8194-2285-1}}{{cite journal| author = W. Heitmann and E. Ritter| title = Production and properties of vacuum evaporated films of thorium fluoride| journal = Appl. Opt.| volume = 7| pages = 307–9| year = 1968| url = http://www.opticsinfobase.org/abstract.cfm?URI=ao-7-2-307| doi = 10.1364/AO.7.000307| pmid = 20062461| issue = 2| bibcode = 1968ApOpt...7..307H| url-access = subscription}} However, like all alpha emitters, thorium is potentially hazardous if incorporated, which means safety should focus on reducing or eliminating this danger. In addition to its radioactivity, thorium is also a chemically toxic heavy metal.
Thorium fluoride was used{{when|date=February 2015}} in making carbon arc lamps, which provided high-intensity illumination for movie projectors and search lights.{{cite book|url=https://books.google.com/books?id=ahNFGR1jMB4C&pg=PA81|page=81|title=Encyclopedia of Chemical Processing and Design: Thermoplastics to Trays, Separation, Useful Capacity|author=McKetta, John J. |publisher=CRC Press|year=1996|isbn=0-8247-2609-X}}[http://www.ibilabs.com/Thorium%20Fluoride-MSDS.htm Thorium tetrafluoride] {{Webarchive|url=https://archive.today/20130216060735/http://www.ibilabs.com/Thorium%20Fluoride-MSDS.htm |date=2013-02-16 }} International Bio-Analytical Industries, Inc.
See also
References
{{reflist}}
{{Thorium compounds}}
{{fluorine compounds}}
{{Actinide halides}}