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Structure and Superconducting Properties of "BeB_2"

D. P. Young·P. W. Adams·J. Y. Chan·F. R. Fronczek
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Abstract

We present the crystal structure and low temperature electronic transport properties of the intermetallic commonly known as BeB_2. In contrast to the much simpler AlB_2-type structure of the 39K superconductor MgB_2, BeB_2 forms a complex structure type that is nearly unique in nature. The structure has 110.5 atoms per unit cell and a stoichiometry BeB_{2.75}. Polycrystalline Be(^{10.8}B)_{2.75} is superconducting below T_c=0.72K with a critical magnetic field H_{c2}=0.175T. Isotopically pure ^{10.0}B samples of have an enhanced$T_c=0.79K, consistent with a BCS isotope effect. Hall effect measurements suggest that the material is intrinsically compensated.

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D. P. Young, P. W. Adams, J. Y. Chan, F. R. Fronczek. 2001-04-06. Structure and Superconducting Properties of "BeB_2". https://doi.org/10.1103/physrevb.65.180518

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