Acta Phys. -Chim. Sin. ›› 2011, Vol. 27 ›› Issue (09): 2227-2232.doi: 10.3866/PKU.WHXB20110916

• PHYSICAL CHEMISTRY OF MATERIALS • Previous Articles     Next Articles

Influence of the Size Effect on the Chemical Shielding Tensors of SiO2 Nanotubes

PU Peng, XU Can, XIE Shu-Yu   

  1. Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000, P. R. China
  • Received:2011-05-23 Revised:2011-06-29 Published:2011-08-26
  • Contact: XU Can E-mail:cxulzu@yahoo.com
  • Supported by:

    The project was supported by the National Science Foundation for Distinguished Young Scholars of China (50925103).

Abstract: Finite length SiO2 nanotubes composed of a three-membered ring (3MR) cross section were investigated by density functional theory. Nuclear magnetic resonance (NMR) results reveal that the isotropic chemical shielding tensor (σiso) and anisotropic chemical shielding tensor (Δσ) of the SiO2 nanotubes oscillate from the terminal end to the intermediate part of the structures with an increase in nanotube lengths, and they tend to reach different stable values. When the length is greater than certain value the σiso and Δσ values obtained from the intermediate part of the finite length nanotube can be used for theoretical predictions of long or infinite length nanotubes. Hence, this investigation is a guide for the selection of reasonable finite length nanotubes to model infinite length nanotubes.

Key words: Nanotube, Nuclear magnetic resonance, Isotropy, Anisotropy, Chemical shielding, Size effect

MSC2000: 

  • O641