View source for UPt3

{{DISPLAYTITLE:UPt<sub>3</sub>}}
{{chembox
| Name = Uranium platinum
| ImageFile = UPt3.svg
| IUPACName = 
| OtherNames = Platinum--uranium (3/1)
|Section1={{Chembox Identifiers
| CASNo_Ref = 
| CASNo = 12311-92-1
| DTXSID = DTXSID90779273
| PubChem = 71354824
| StdInChI=1S/3Pt.U
| StdInChIKey = YYBWTXHBZRZQRM-UHFFFAOYSA-N
| SMILES = [Pt].[Pt].[Pt].[U]
}}
|Section2={{Chembox Properties
| Formula = UPt<sub>3</sub>
| MolarMass = 823.3 g/mol<ref name="PubChem">{{Cite web |last=PubChem |title=Platinum--uranium (3/1) |url=https://pubchem.ncbi.nlm.nih.gov/compound/71354824 |access-date=2022-10-18 |website=pubchem.ncbi.nlm.nih.gov |language=en}}</ref>
| Density = 19.3 g/cm<sup>3</sup>
| MeltingPt = 1700°C<ref name="Lyakishev">{{Cite book |title=Диаграммы состояния двойных металлических систем |page=448 |language=russian |trans-title=State diagrams of binary metal systems |series=Mechanical Engineering |year=2001 |volume=3, book 3 |location=Moscow |isbn=5-217-02932-3 |editor-last=Lyakishev |editor-first=N.P.}}</ref>
}}
|Section3={{Chembox Structure
| CrystalStruct = ''see text''
| SpaceGroup =  P6<sub>3</sub>/mmc
| Coordination = 
}}
|Section4={{Chembox Thermochemistry
| Entropy = -111 J·mol<sup>−1</sup>·K<sup>−1</sup><ref name="Kleykamp">{{Cite magazine |last=Kleykamp |first=Heiko |date=1991 |title=Thermodynamics of the uranium-platinum metals systems |url=http://publications.iupac.org/pac/63/10/1401/index.html |magazine=Pure and Applied Chemistry |language=en |volume=63 |issue=10 |pages=1401–1408 |doi=10.1351/pac199163101401 |archive-url=https://web.archive.org/web/20150214104223/http://pac.iupac.org/publications/pac/pdf/1991/pdf/6310x1401.pdf |archive-date=14 February 2015 |access-date=2022-10-17}}</ref>
 }}
}}

'''UPt<sub>3</sub>''' is an inorganic binary [[intermetallic]] [[crystalline]] compound of [[platinum]] and [[uranium]].<ref name="PubChem"/>

== Production ==
It can be synthesised in the following ways:<ref name="Kleykamp"/>
* as an intermetallic compound, by direct fusion of pure components according to [[stoichiometric]] calculations:

:: <math>\mathsf{ 3 Pt + U \ \xrightarrow{1700^oC}\ UPt_3 }</math>

* by reduction of [[uranium dioxide]] with [[hydrogen]] in the presence of platinum:

:: <math>\mathsf{ UO_2 + 2 H_2 + 3 Pt \ \xrightarrow{1700^oC}\ UPt_3 + 2 H_2O }</math>

== Physical properties ==
UPt<sub>3</sub> forms crystals of [[Hexagonal crystal family|hexagonal symmetry]] (some studies hypothesize a trigonal structure instead<ref>{{Cite magazine |last1=Walko |first1=D. A. |last2=Hong |first2=J.-I. |last3=Chandrasekhar Rao |first3=T. V. |date=2001-01-16 |title=Crystal structure assignment for the heavy-fermion superconductor UPt<sub>3</sub> |url=https://link.aps.org/doi/10.1103/PhysRevB.63.054522 |magazine=Physical Review B |volume=63 |issue=5 |pages=054522 |doi=10.1103/PhysRevB.63.054522 |access-date=2022-10-18}}</ref>), [[space group]] P6<sub>3</sub>/mmc,<ref>{{Cite journal |last1=Sumita |first1=Shuntaro |last2=Yanase |first2=Youichi |date=2018-04-13 |title=Unconventional superconducting gap structure protected by space group symmetry |journal=Physical Review B |volume=97 |issue=13 |pages=134512 |doi=10.1103/PhysRevB.97.134512|arxiv=1801.03293 |bibcode=2018PhRvB..97m4512S |s2cid=119100443 }}</ref> cell parameters ''a'' = 0.5766 nm and ''c'' = 0.4898 nm (''c'' should be understood as distance from planes), with a structure similar to [[nisnite]] (Ni<sub>3</sub>Sn) and MgCd<sub>3</sub>.<ref>{{Cite book |surname=Predel |title=Ni-Np – Pt-Zr |chapter-url=https://dx.doi.org/10.1007/10542753_2536 |chapter=Pt-U (Platinum-Uranium) |series=Landolt-Börnstein - Group IV Physical Chemistry |year=1998 |publisher=Springer-Verlag |isbn=3-540-61712-4 |pages=1–2 |language=en |doi=10.1007/10542753_2536}}</ref><ref>{{Cite magazine |last1=Ross |first1=B. A. S. |last2=Peterson |first2=D. E. |date=1990-06-01 |title=The Pt-U (Platinum-Uranium) system |url=https://doi.org/10.1007/BF03029291 |magazine=Bulletin of Alloy Phase Diagrams |language=en |volume=11 |issue=3 |pages=240–243 |doi=10.1007/BF03029291 |access-date=2022-10-09}}</ref>

The compound [[Congruent melting|congruently melts]] at 1700 °C.<ref name="Lyakishev"/> The [[enthalpy of formation]] of the compound is -111 kJ/mol.<ref name="Kleykamp"/>

At temperatures below 1 [[Kelvin|K]] it becomes [[Superconductivity|superconducting]], thought to be due to the presence of [[Heavy fermion superconductor|heavy fermions]] (the uranium atoms).<ref>{{Cite magazine |last1=Gurtovoy |first1=К. G. |last2=Levitin |first2=R. Z. |date=October 1987 |title=Магнетизм актинидов и их соединений |trans-title=Magnetism of actinides and their compounds |url=https://ufn.ru/ufn87/ufn87_10/Russian/r8710b.pdf |magazine=Успехи физических наук (Advances in the Physical Sciences) |volume=153 |issue=2 |access-date=2022-10-09}}</ref><ref>{{Cite magazine |last=Mineev |first=V. P. |date=1994 |title=Superconductivity in UPt3 |url=https://www.annphys.org/articles/anphys/abs/1994/04/anphys_1994__19_4_367_0/anphys_1994__19_4_367_0.html |magazine=Annales de Physique |language=en |volume=19 |issue=4 |pages=367–384 |doi=10.1051/anphys:01994001904036700 |access-date=2022-10-09}}</ref>

==References==
{{Reflist}}

{{Platinum compounds}}
{{Uranium compounds}}

[[Category:Platinum compounds]]
[[Category:Uranium compounds]]
[[Category:Intermetallics]]