title: CoBi3--the first binary compound of cobalt with bismuth: high-pressure synthesis and superconductivity.
abstract: The first compound in the cobalt bismuth system was synthesized by high-pressure high-temperature synthesis at 5 GPa and 450 °C. CoBi3 crystallizes in space group Pnma (no. 62) with lattice parameters of a = 8.8464(7) Å, b = 4.0697(4) Å and c = 11.5604(9) Å adopting a NiBi3-type crystal structure. CoBi3 undergoes a superconducting transition at Tc = 0.48(3) K as evidenced by electrical-resistivity and specific-heat measurements. Based on the anomaly of the specific heat at Tc and considering the estimated electron-phonon coupling, the new Bi-rich compound can be classified as a Bardeen-Cooper-Schrieffer-type superconductor with weak electron-phonon coupling. Density-functional theory calculations disclose a sizable influence of the spin-orbit coupling to the valence states and proximity to a magnetic instability, which accounts for a significantly enhanced Sommerfeld coefficient.
authors.affiliation: CNRS, ICMCB, UPR 9048, F-33600 Pessac, France. Univ. Bordeaux, ICMCB, UPR 9048, F-33600 Pessac, France.
authors.forename: S
authors.initials: S
authors.lastname: Tencé
authors.forename: O
authors.initials: O
authors.lastname: Janson
authors.forename: C
authors.initials: C
authors.lastname: Krellner
authors.forename: H
authors.initials: H
authors.lastname: Rosner
authors.forename: U
authors.initials: U
authors.lastname: Schwarz
authors.forename: Y
authors.initials: Y
authors.lastname: Grin
authors.forename: F
authors.initials: F
authors.lastname: Steglich