论文标题
评论“ Pentadiamond：SP2和SP3原子的五角大楼网络的硬碳同素同形”
Comment on "Pentadiamond: A Hard Carbon Allotrope of a Pentagonal Network of sp2 and sp3 atoms"
论文作者
论文摘要
在最近的字母[1] Y. Fujii等人中。提出了一种新的碳同质量，并分别宣称其极高的Young和剪切模量分别为1691年和1113 GPA，使钻石的超过1.5和2次超过钻石！作者还声称，该碳修饰的独特平均泊松比为-0.24，散装模量为381 GPA，声速为28.7 km/s的记录值。在这里，我们通过两个独立的计算显示这些值是由于错误而获得的。实际上，新的假设同种素具有相当中等的弹性模量，对于具有相似密度的碳结构而言，它并不像：250 GPA的大量模量，170 GPA的剪切模量，Young的417 GPA模量，阳性Poisson的阳性比率为0.22。
In a recent Letter [1] Y. Fujii et al. proposed a new carbon allotrope and claimed its extremely high Young's and shear moduli of 1691 and 1113 GPa, respectively, surpassing those of diamond by 1.5 and 2 times! The authors also claimed unique negative averaged Poisson's ratio of -0.24, bulk modulus of 381 GPa and record value of the sound speed 28.7 km/s for this carbon modification. Here we show by two independent computations that these values were obtained as a result of errors. The new hypothetical allotrope has in fact quite moderate elastic moduli, unremarkable for a carbon structure with similar density: bulk modulus of 250 GPa, shear modulus of 170 GPa,Young's modulus of 417 GPa, positive Poisson's ratio of 0.22.
