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Compressibility and Electronic Structure of MgB2 up to 8 GPa

T. Vogt·G. Schneider·J. A. Hriljac·G. Yang·J. S. Abell
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Abstract

The lattice parameters of MgB2 up to pressures of 8 GPa were determined using high-resolution x-ray powder diffraction in a diamond anvil cell. The bulk modulus, B0, was determined to be 151 +-5 GPa. Both experimental and first-principles calculations indicate nearly isotropic mechanical behavior under pressure. This small anisotropy is in contrast to the 2 dimensional nature of the boron pi states. The pressure dependence of the density of states at the Fermi level and a reasonable value for the average phonon frequency account within the context of BCS theory for the reduction of Tc under pressure.

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T. Vogt, G. Schneider, J. A. Hriljac, G. Yang, J. S. Abell. 2001-02-27. Compressibility and Electronic Structure of MgB2 up to 8 GPa. https://doi.org/10.1103/physrevb.63.220505

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