Ozone addition to C60 and C70 fullerenes: a DFT study
D Sh Sabirov1, S L Khursan, R G Bulgakov
1Physical Chemistry Problems Laboratory, Institute of Petrochemistry and Catalysis RAS, Ufa 450075, Russia.
Abstract:
Three modes of synchronous ozone addition ([6.6]-, [5.6]-, and 1,4-addition) to C(60) fullerene and three modes of ozone addition to C(70) (ab-, cc-, and de-addition) have been studied using density functional theory calculations. Comparison of activation enthalpies shows that in the case of C(60), [6.6]-addition of ozone is the most favorable energetically and occurs without a barrier. In the case of the C(70) fullerene, additions to ab- and cc-bonds are the most favorable. The initial step of interaction between a C(60)/C(70) and O(3) is the formation of a molecular complex, which then converts into a primary ozonide. The calculated rate constant of the [6.6]-addition to the C(60) fullerene according to the proposed scheme is 3.90 x 10(6)L mol(-1)s(-1), which corresponds well to the experimental value.
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