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arXiv · 0811.1282

Face-Centered-Cubic B$_{80}$ Metal: Density functional theory calculations

Qing-Bo Yan·Qing-Rong Zheng·Gang Su
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Abstract

By means of ab initio calculations within the density functional theory, we have found that B80 fullerenes can condense to form stable face-centered-cubic fcc solids. It is shown that when forming a crystal, B80 cages are geometrically distorted, the Ih symmetry is lowered to Th, and four boron-boron chemical bonds are formed between every two nearest neighbor B80 cages. The cohesive energy of B80 fcc solid is 0.23 eV/atom with respect to the isolated B80 fullerene. The calculated electronic structure reveals that the fcc B80 solid is a metal. The predicted solid phase would constitute a form of pure boron and might have diverse implications. In addition, a simple electron counting rule is proposed, which could explain the stability of B80 fullerene and the recently predicted stable boron sheet.

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Qing-Bo Yan, Qing-Rong Zheng, Gang Su. 2008-11-08. Face-Centered-Cubic B$_{80}$ Metal: Density functional theory calculations. https://doi.org/10.1103/physrevb.77.224106

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