Identification of the crystal structures of two superconducting phases for potassium-doped picene

Xun-Wang Yan; Zhongbing Huang; Hai-Qing Lin

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arXiv · 1407.0747

Identification of the crystal structures of two superconducting phases for potassium-doped picene

Xun-Wang Yan·Zhongbing Huang·Hai-Qing Lin

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Abstract

By the first principles calculations and X-ray diffraction simulations, we perform a systematic study of multiple superconducting phases of potassium-doped picene [Nature {\bf464} 76, 2010]. The combination of optimized lattice parameters, formation energy, and simulated X-ray diffraction spectra indicates that the superconducting phase with transition temperature (T$_c$) of 7 K corresponds to a charge doped K$_2$picene, which is semiconducting with a 0.1 eV energy gap, while the superconducting phase with T$_c$=18 K corresponds to a metallic K$_3$picene. The distinct crystal and electronic structures of K$_2$picene and K$_3$picene provide a reasonable explanation of two superconducting phases in potassium-doped picene.

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Xun-Wang Yan, Zhongbing Huang, Hai-Qing Lin. 2014-07-03. Identification of the crystal structures of two superconducting phases for potassium-doped picene. https://arxiv.org/abs/1407.0747

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