Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z1, Canada.
Nanoscale. 2010 Feb;2(2):254-61. doi: 10.1039/b9nr00159j. Epub 2009 Oct 22.
The geometries, chemical shifts, aromaticity, and reactivity of finite-length open-ended armchair single-walled carbon nanotubes (SWCNTs) have been studied within density functional theory. The widely used model of capping hydrogen atoms at the open ends of a SWCNT changes the chemical activity of the SWCNT and destabilizes the frontier molecular orbitals. The edge pi-orbital of the open ends enhances both pi- and sigma-aromaticity of the first belt of hexagons of carbon atoms at the open ends. The effect of the open ends on the structure and chemical reactivity of the SWCNT reaches only the first several layers of the hexagons of carbon atoms. Additions of carbene and dichlorocarbene to the nanotube reveal that the open ends have higher reactivities than the inner regions.
在密度泛函理论的框架下，研究了有限长度开口扶手椅型单壁碳纳米管（SWCNT）的几何形状、化学位移、芳香性和反应性。在 SWCNT 的开口端用氢原子封端的广泛使用的模型改变了 SWCNT 的化学活性，并使前沿分子轨道失稳。开口端的边缘 pi 轨道增强了开口端碳原子的第一排六边形的 pi 和 sigma 芳香性。开口端对 SWCNT 的结构和化学反应性的影响仅到达碳原子的六边形的前几层。碳烯和二氯卡宾添加到纳米管中表明，开口端比内部区域具有更高的反应活性。
