Shi Xizhi, Li Shifang, Li Jin, Ouyang Tao, Zhang Chunxiao, Tang Chao, He Chaoyu, Zhong Jianxin
Hunan Key Laboratory of Micro-Nano Energy Materials and Devices, Xiangtan University, Xiangtan, Hunan411105, P. R. China.
Laboratory for Quantum Engineering and Micro-Nano Energy Technology and School of Physics and Optoelectronics, Xiangtan University, Xiangtan, Hunan 411105, P. R. China.
J Phys Chem Lett. 2021 Dec 2;12(47):11511-11519. doi: 10.1021/acs.jpclett.1c03193. Epub 2021 Nov 19.
The configurational space of two-dimensional planar sp carbon has been systematically scanned by a random strategy combined with group and graph theory, and 1114 new carbon allotropes have been identified. These allotropes are energetically more favorable than most of the previously predicted 120 carbon allotropes. By fitting the HSE06 band structures of six old structures, we optimize the parameters for a general and transferable tight-binding model for high-throughput band structure calculations. We identified that there are 190 Dirac semimetals, 241 semiconductors, and 683 normal metals among the new allotropes. Interestingly, several stable low-energy carbon systems with exotic electronic properties are proposed, such as type III, type I/II mixed, and type I/III mixed semimetals, which are very rare in planar carbon systems. In particular, one nodal-line semimetal has been discovered among these thousands of allotropes, which is the first nodal-line semimetal in sp carbon systems. Our discoveries greatly enrich our knowledge of the structures and electronic properties of the two-dimensional carbon family.
通过结合群论和图论的随机策略，对二维平面sp碳的构型空间进行了系统扫描，已识别出1114种新的碳同素异形体。这些同素异形体在能量上比大多数先前预测的120种碳同素异形体更有利。通过拟合六种旧结构的HSE06能带结构，我们优化了用于高通量能带结构计算的通用且可转移的紧束缚模型的参数。我们确定在新的同素异形体中有190种狄拉克半金属、241种半导体和683种普通金属。有趣的是，提出了几种具有奇异电子性质的稳定低能碳体系，如III型、I/II混合型和I/III混合型半金属，这些在平面碳体系中非常罕见。特别是，在这数千种同素异形体中发现了一种节线半金属，这是sp碳体系中的首个节线半金属。我们的发现极大地丰富了我们对二维碳族结构和电子性质的认识。
