Primitive unit cell of the new ground-state structure for boron, τ-B₁₀₅, viewed along the [010] direction. B₁₂ units are shown in green, B₂₈ units in orange, and the B13 site is shown in purple.

From the article:

New Ground-State Crystal Structure of Elemental Boron
Qi An, K. Madhav Reddy, Kelvin Y. Xie, Kevin J. Hemker, and William A. Goddard, III
Phys. Rev. Lett. 117, 085501 (2016)

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