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arXiv 1502.04323cond-mat.mes-hall
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石墨在沿c轴的单轴压缩下:一个新的将面外应变与面内声子频率联系起来的参数

Graphite under uniaxial compression along c-axis: a new parameter relates out-of-plane strain to in-plane phonon frequency

Y. W. Sun, D. Holec, D. J. Dunstan

摘要:

堆叠石墨烯片形成石墨。从石墨烯的E2g模出发,推导出了石墨的两个面内振动模E1u和E2g(2),并将其在压缩条件下的位移视为面内键缩短的结果。Gr值Uneisen参数已经被报道用于量化这种关系。然而,为什么这三种模式与压力的变化率不同的原因尚不清楚。在这项工作中,我们引入了一个新的参数来量化面外应变对面内振动频率的贡献,这表明π电子的压缩在高压下的石墨和石墨烯中都起着不可忽视的作用。

英文摘要:

Stacking graphene sheets forms graphite. Two in-plane vibrational modes of graphite, E1u and E2g(2), are derived from graphene E2g mode, the shifts of which under compression are all considered as results of in-plane bond shortening. Values of Gruneisen parameter have been reported to quantify such relation. However, the reason why the shift rates of these three modes with pressure differ is unclear. In this work, we introduce a new parameter to quantify the contribution of out-of-plane strain to the in-plane vibrational frequencies, suggesting that the compression of π-electrons plays a non-negligible part in both graphite and graphene under high pressure.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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