Theoretical studies on structures, electronic spectra and nonlinear optical properties of isoxazolo-fullerene derivatives

The AMI semiempirical calculation method was employed to study the structures and electronic properties of a series of isoxazolo-fullerene derivatives. Based on the AMI geometry optimization, the electronic spectra of molecules were studied by using ZINDO/CIS methods. The results indicated the HOMO-LUMO energy gaps of those isoxazolo-fullerenes were lower than that of C(60). There existed the intramolecular electron transfer from the additional section to C(60) moiety. The electronic spectrum data showed that the exception of the absorption was beyond 400 nm. The results were in good accordance with the experiment results. Nonlinear optical susceptibilities alpha, beta and gamma of molecules were calculated according to Finite Field (FF)/AM1, and the influence of molecular structures on nonlinear optical properties was examined.