Patterns for addition to C59BHElectronic supplementary information (ESI) available: Heats of formation and single-point energies for heterofullerenes. See http://www.rsc.org/suppdata/cp/b3/b300458a/

Abstract

Semiempirical AM1 and MNDO methods are used to examine the relative stability of the different isomers of C59BHX2n (X = H, F; n = 1,2). The energies show that the most stable isomer of C59BH3 is the 5,6-isomer, which is a 1,2-adduct of C59BH; however, for C59BH5, 7,24,11,27-isomer is the most energetically preferred structure, which is a 1,4/1,4-adduct of C59BH. The addition patterns of C59BHF2 is different from that of C59BH3, 7,24-isomer (a 1,4-adduct of C59BH), is the lowest energy structure, while for C59BHF4, the most energetically preferred structure corresponds to 7,24,11,27-isomer of C59BH5. Comparing the patterns for addition to C59BH and to C59HN, the calculation results indicate that the regioselectivity of this type of heterofullerenes is not only related to the doping heteroatom but also related to the adding group. The NICS of some isomers' are calculated for comparing their aromaticity. The predicted NICS values indicate that aromaticity may be the primary factor to stabilize the 1,2- and 1,4-adducts of C59BH.