THE JAHN-TELLER DISTORTION OF SEVERAL C-7 0(N) IONS AND ELECTRONIC-SPECTRA FOR SINGLETS

The INDO methods were used to perform theoretical studies for C-70(n)( n = +2, +1, -1, -2, -3 and -4). It was shown that the Jahn-Teller dist ortion has taken place for C-70(n) except for C-70(2+) triplet (D-5h), which results in the lowering of symmetry to C-2v and produces 30 kin ds of bonds and 21 unique carbon atoms. Based on the optimised geometr ies, the electronic spectrum for C-70(4-) singlet was calculated, the NIR absorptions of which are good agreement with the experimental resu lts. Meanwhile the electronic spectrum for C-70(2+) singlet was predic ted.