A computational NICS and C-13 NMR characterization of BN-substituted C-60 fullerenes

作者：Anafcheh Maryam; Hadipour Nasser L^*

来源：Physica E: Low-Dimensional Systems and Nanostructures , 2011, 44(2): 400-404.

DOI：10.1016/j.physe.2011.09.005

DFT calculations are applied to devise NMR parameters of heterofullerenes C60-2x(BN)(x) (x=1, 2, 3, 6, 9, 12, 15, 18, 21, and 24). The calculated chemical shielding tensors at the sites of C-13 nuclei in the first and second neighbor of the doped atoms are perturbed and other distant atoms are not influenced significantly. Chemical shielding of the second neighbor of nitrogen and boron nuclei is significantly shifted to upfield and downfield (the second neighboring effect), respectively. Nucleus independent chemical shifts (NICS) at the cage center of BN-substituted fullerenes demystifies that substituted species are more aromatic than C-60. The predicted NICS values may be useful for identification of the heterofullerenes through their endohedral He-3 NMR chemical shifts.

• 出版日期2011-11