Theoretical explorations on BN-doped armchair single-walled carbon nanotubes

• Published in: Journal of molecular structure. Theochem 2006-06, Vol.765 (1), p.1-11
• Main Authors: Zhang, Chong, Li, Ruifang, Zhang, Dongju, Shang, Zhenfeng, Wang, Guichang, Liang, Yunxiao, Xing, Yumei, Pan, Yinming, Cai, Zunsheng, Zhao, Xuezhuang, Liu, Chengbu
• Format: Article
• Language: English
• Subjects: Armchair single-walled carbon nanotubes (ASWCNTs); BN doping; Geometries; Redox and excitation energies
• ISSN: 0166-1280; 1872-7999
• DOI: 10.1016/j.theochem.2005.12.002

The geometries and stabilities of mono-BN doped (5,5) armchair single-walled carbon nanotube (ASWCNT) isomers for a smaller C 50H 20 model are first investigated by both AM1 and HF/4-31G methods. The calculations suggest that both the two methods obtain similar results, demonstrating that the AM1 method is reliable in calculating the properties of BN-doped ASWCNT isomers. Then, the equilibrium structures and relative stabilities of the mono-, di-, and tri-BN doped isomers for a larger (5,5) ASWCNT model (C 110H 20) are further studied based on AM1 level. For mono-BN doped ASWCNT, the thermodynamic stabilities of its isomers in general decrease with the separation between two heteroatoms, and the isomer with two neighbored B and N atoms is the most stable one. For di- or tri-BN doped ASWCNT isomers, the N–N and B–B bonds should be avoided and the isomer with a B–N–B–N or B–N–B–N–B–N chain in same hexagon is the most stable one. The BN-doping generally enhances the redox and electron excitation properties of BN-doped ASWCNT isomers compared with their host tube, and their stabilities increase with their diameter enlargement on the whole.