DFT study of NH₃ adsorption on the (5,0), (8,0), (5,5) and (6,6) single-walled carbon nanotubes. Calculated binding energies, NMR and NQR parameters

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• 作者：Bahram B. Shirvani ; Javad Beheshtian ; Mehdi D. Esrafili ; Nasser L. Hadipour
• 关键词：Single-walled carbon nanotube ; Binding energy ; Chemical shielding ; NMR ; NQR ; DFT
• 刊名：Physica B
• 出版年：2010
• 出版时间：15 March 2010
• 年：2010
• 卷：405
• 期：6
• 页码：1455-1460
• 全文大小：514 K

文摘

Behavior of a single NH₃ molecule adsorbed on external surface of H-capped (5,5), (6,6), (5,0), and (8,0) single-walled carbon nanotubes (SWCNTs) is studied via DFT calculations. Binding energies clearly exhibit adsorption dependence on tube diameter. ¹³C, ¹⁵N and ¹H chemical shielding tensors are calculated at the B3LYP level using GIAO method. NMR calculations reveal that ¹³C chemical shielding of (8,0) is more sensitive to NH₃ adsorption compared to (5,5), (6,6) and (5,0) tubes. ¹⁵N and ¹H chemical shielding correlate noticeably with diameter of the nanotubes. ¹⁴N and ²H nuclear quadrupole coupling constants, C_Q, and asymmetry parameter, η, reveal the remarkable effect of NH₃ adsorption on electronic structure of the SWCNTs.