Theoretical Structural and Spectral Analyses of TEMPO Radical Derivatives of Fullerene

Document Type : Research Paper


Department of Physics, Faculty of Arts and Sciences, Süleyman Demirel University, 32260 Isparta, Turkey


The spectroscopic properties of the 2,2,6,6-tetramethyl-piperidine-1-oxyl (TEMPO) radical
derivatives of the fullerene (C60) were theoretically investigated. The ground state optimized
structures of the radical adducts of the fullerene were calculated by using DFT (B3LYP) with 6-31
G(d) level. It was concluded that a 6-6 ring junction of C60 moiety generally covalently links to the
piperidine ring of the TEMPO derivatives, directly. The optimization characteristics of all the
fullerene radical derivatives indicate generally a annulene structure while C60+TEMPO indicate a
cyclopropane structure which is formed by the link of the carbon of the piperidine ring doubly to a 6-
6 ring junction of C60. The calculated isotropic hyperfine coupling constants, vibrational frequencies
and UV- Vis transition energies of all the radical adducts were seen to be in good agreement with the
corresponding experimental data. The UV-Vis transitions and their energies were determined with
corresponding to the experimental values. In the IR analysis the shifts of vibrational frequencies have
been commented by comparison with those belonged to the pure C60. Also the some selected
geometrical parameters with together the cage width and the cage length for the ground state
optimized structures of all the radical adducts were listed, and the binding energies of the radicals
were obtained.