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Atomic structure and vibrational properties of icosahedral B$_4$C boron carbide

R. Lazzari·N. Vast·J. M. Besson·S. Baroni·A. Dal Corso
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Abstract

The atomic structure of icosahedral B$_4$C boron carbide is determined by comparing existing infra-red absorption and Raman diffusion measurements with the predictions of accurate {\it ab initio} lattice-dynamical calculations performed for different structural models. This allows us to unambiguously determine the location of the carbon atom within the boron icosahedron, a task presently beyond X-ray and neutron diffraction ability. By examining the inter- and intra-icosahedral contributions to the stiffness we show that, contrary to recent conjectures, intra-icosahedral bonds are harder.

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R. Lazzari, N. Vast, J. M. Besson, S. Baroni, A. Dal Corso. 1999-09-13. Atomic structure and vibrational properties of icosahedral B$_4$C boron carbide. https://doi.org/10.1103/physrevlett.83.3230

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