title: Superconductivity of metallic boron in MgB2.
abstract: Boron in MgB2 forms stacks of honeycomb layers with magnesium as a space filler. Band structure calculations indicate that Mg is substantially ionized, and the bands at the Fermi level derive mainly from B orbitals. Strong bonding with an ionic component and considerable metallic density of states yield a sizable electron-phonon coupling. Together with high phonon frequencies, which we estimate via zone-center frozen phonon calculations to be between 300 and 700 cm(-1), this produces a high critical temperature, consistent with recent experiments. Thus MgB2 can be viewed as an analog of the long sought, but still hypothetical, superconducting metallic hydrogen.
authors.affiliation: Georgetown University, Washington, D.C. 20057 and Center for Computational Materials Science, Code 6390, Naval Research Laboratory, Washington, D.C. 20375.
authors.forename: J
authors.initials: J
authors.lastname: Kortus
authors.forename: I I
authors.initials: II
authors.lastname: Mazin
authors.forename: K D
authors.initials: KD
authors.lastname: Belashchenko
authors.forename: V P
authors.initials: VP
authors.lastname: Antropov
authors.forename: L L
authors.initials: LL
authors.lastname: Boyer