星际碳纳米管的吸收光谱  

Absorption spectrum of carbon nanotubes in the space

作　　者：陈秀慧 李爱根[2] 蔡剑华[1] 杨江河[1] 庹满先[1] CHEN XiuHui;LI AiGen;CAI JianHua;YANG JiangHe;TUO ManXian(College of Mathematics and Physics,Hunan University of Arts and Science,Changde 415000,China;Department of Physics and Astronomy,University of Missouri,Columbia 65211,USA)

机构地区：[1]湖南文理学院数理学院,常德415000 [2]美国密苏里大学物理和天文学系,哥伦比亚65211,美国

出　　处：《中国科学：物理学、力学、天文学》2022年第11期145-149,共5页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：湖南文理学院博士科研启动基金项目(编号:19BSQD38);湖南文理学院项目(编号:19YB15)资助;国家自然科学基金天文联合基金项目(编号:U2031112);湖南省自然科学基金(编号:2021JJ30469);湖南省教育厅项目(编号:19C1263)。

摘　　要：近年来,石墨烯C_(24)在星际空间中通过其红外振动光谱而得以证认.因为石墨烯片卷曲可能形成碳纳米管(Carbon Nanotube,CNT),搜寻星际碳纳米管成为空间紫外和红外望远镜的重要关注点.本文采用离散偶极子近似方法计算最小的CNT—(5,0)CNT—在紫外、可见光和近红外波长范围内的吸收光谱.结果显示有四个比较明显的特征峰,它们的波长分别为∼0.3,∼0.5,∼0.9和∼2.9μm.随着CNT的增长,峰值吸收光谱的波长向红端移动.当管长达到23个或更多碳原子后,∼2.9μm特征峰变得异常的强.计算表明,为确保计算精度,偶极子数目应不少于C–C键数的10倍.Graphene Cwas recently identified in interstellar space through its characteristic infrared vibrational spectra. As graphene can bend to form carbon nanotubes(CNTs), one of the focuses of ultraviolet and infrared space telescopes is to search for interstellar CNTs. Here, we calculate the absorption spectrum of(5, 0) CNT, the smallest CNT, using the discrete dipole approximation.(5, 0) CNT exhibits four spectral features, peaking at ~0.3, ~0.5, ~0.9, and ~2.9 μm, with the peak wavelengths shifting toward the red region with the increasing tube length. When the tube length is longer than23 carbon atoms, the ~2.9 μm peak becomes quite prominent. Moreover, the absorption spectrum converges if the number of dipoles is at least ten times that of the C–C bonds.

关 键 词：碳纳米管 吸收光谱 星际介质 宇宙尘埃 

分 类 号：TQ127.11[化学工程—无机化工] O641.1[理学—物理化学] V447[理学—化学]