Magnesium diboride

Magnesium diboride

Identifiers
CAS Number	12007-25-9 Y
3D model (JSmol)	Interactive image Interactive image
ChemSpider	13118398 N
ECHA InfoCard	100.031.352
EC Number	234-501-2
PubChem CID	15987061
CompTox Dashboard (EPA)	DTXSID60893677
InChI InChI=1S/2B.Mg N Key: PZKRHHZKOQZHIO-UHFFFAOYSA-N N
SMILES [B-]=[B-].[Mg+2] [Mg+2].[Mg+2].[Mg+2].[Mg+2].[Mg+2].[Mg+2].[B-]1=[B-][B-]2=[B-][B-]=[B-]3[B-]=[B-][B-]4=[B-][B-]=[B-]5[B-]=[B-][B-]6=[B-][B-]=[B-]1[B-]7=[B-]2[B-]3=[B-]4[B-]5=[B-]67.[Mg+2].[Mg+2].[Mg+2].[Mg+2].[Mg+2].[Mg+2]
Properties
Chemical formula	MgB2
Molar mass	45.93 g/mol
Density	2.57 g/cm3
Melting point	830 °C (1,530 °F; 1,100 K) (decomposes)
Structure
Crystal structure	Hexagonal, hP3
Space group	P6/mmm, No. 191
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Magnesium diboride is the inorganic compound with the formula MgB₂. It is a dark gray, water-insoluble solid. The compound has attracted attention because it becomes superconducting at 39 K (−234 °C). In terms of its composition, MgB₂ differs strikingly from most low-temperature superconductors, which feature mainly transition metals. Its superconducting mechanism is primarily described by BCS theory.