Yeh Chia-Nan, Wu Can, Su Haibin, Chai Jeng-Da
Department of Physics, National Taiwan University Taipei 10617 Taiwan
School of Materials Science and Engineering, Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Republic of Singapore
RSC Adv. 2018 Oct 8;8(60):34350-34358. doi: 10.1039/c8ra01336e. eCollection 2018 Oct 4.
To fully utilize the great potential of graphene in electronics, a comprehensive understanding of the electronic properties of finite-size graphene flakes is essential. While the coronene series with fused benzene rings at each side (designated as -coronenes) are possible structures for opening a band gap in graphene, their electronic properties are not yet fully understood. Nevertheless, because of their radical character, it remains very difficult to reliably predict the electronic properties of the larger -coronenes with conventional computational approaches. In order to circumvent this, the various electronic properties of -coronenes ( = 2-11) are investigated using thermally-assisted-occupation density functional theory (TAO-DFT) [J.-D. Chai, , 2012, , 154104], a very efficient electronic structure method for studying nanoscale systems with strong static correlation effects. The ground states of the larger -coronenes are shown to be polyradical singlets, where the active orbitals are mainly localized at the zigzag edges.
为了充分利用石墨烯在电子学中的巨大潜力，全面了解有限尺寸石墨烯薄片的电子特性至关重要。虽然在每一侧具有稠合苯环的蔻系列（称为-蔻）是在石墨烯中打开带隙的可能结构，但其电子特性尚未完全了解。然而，由于它们的自由基特性，使用传统计算方法可靠预测较大的-蔻的电子特性仍然非常困难。为了规避这一问题，使用热辅助占据密度泛函理论（TAO-DFT）[J.-D.柴，，2012，，154104]研究了-蔻（= 2-11）的各种电子特性，TAO-DFT是一种用于研究具有强静态相关效应的纳米级系统的非常有效的电子结构方法。结果表明，较大的-蔻的基态是多自由基单重态，其中活性轨道主要定域在锯齿边缘。
