Study on the optical and magnetic properties of C48N12 azafullerene isomers

Abstract

The nonlinear optical properties, IR and Raman frequencies as well as NMR chemical shifts of two S₆ symmetrical C₄₈N₁₂ azafullerene isomers (I and II conformations) were calculated and compared with those of C₆₀ at the B3LYP/6-31G* level of density functional theory. The second order hyperpolarizabilities were determined by means of ZINDO/SOS. The static (hyper)polarizabilities of C₄₈N₁₂ are smaller than those of C₆₀, whereas the DC-electric field induced second harmonic generation of II is 58% larger than that of C₆₀ at the frequency of 1.1653 eV, suggesting that II is a potential NLO candidate. In contrast to I, all five of the most intense IR and Raman frequencies of II exceed 1000 cm⁻¹. These differences, and those between the computed ¹³C NMR chemical shifts of I and II should be useful to distinguish and to identify these two structural isomers.