Organometallic chemistry of new carbon materials. Structure and dynamic behavior of group 6 metal tricabonyl complexes of graphene and perforated graphene: a DFT study

International audience; The mechanism of inter-ring haptotropic rearrangements (IRHRs) was investigated by DFT for the tricarbonyl eta(6)-complexes of group 6 metals (M = Cr, Mo, W) of coronene (I-M), kekulene (II-M) and a model graphene (III-M). The computed eta(6),eta(6)-IRHR activation barriers in the middle size PAHs I-M and II-M were calculated to be substantially lower than those in the case of complexes of relatively small size PAHs such as naphthalene chromium tricarbonyl (Delta G approximate to 20-25 kcal mol(-1)vs. approximate to 30 kcal mol(-1)). The barrier is further lowered in the case of the model graphene complex III-Cr (Delta G approximate to 13 kcal mol(-1)). An even lower barrier is found for III-Mo (Delta G approximate to 10 kcal mol(-1)), whereas it slightly increases for III-W (Delta G approximate to 14 kcal mol(-1)).