Density functional theory on 13C NMR chemical shifts of fullerene

Abstract

13C NMR chemical shifts of pristine fullerene have been studied computationally using gauge–independent atomic orbital (GAIO) and density functional theory (DFT). The molecular structure of C60 were optimized by DFT/B3LYP method with 6-31G basis set using Gaussian 09 program. The shielding constants for 13C atom have been calculated by GIAO/B3LYP/6-31G(d,p) approach and analyzed both in gas and solvent phases. The solvent effect is mimicked by PCM polarizable continuum model. A single sharp line in the nuclear magnetic resonance spectrum is observed. The NMR spectra of the investigated compound are in good agreement with the structures optimized by DFT calculations. With the shielding magnetic tensor (GIAO), the magnetic shielding density and magnetically induced current density with the mapped surface for the nucleus of the molecule were simulated and analyzed. The results indicate that the complete information may be obtained from 13C NMR of pristine fullerene. The high symmetrical nature of the sample paves way for designing the bioactive materials which will be useful in the field of carbon nano medicine and targeted drug delivery applications.