Organometallic chemistry of new carbon materials. Structure and dynamic behavior of group 6 metal tricabonyl complexes of graphene and perforated graphene: a DFT study†
The mechanism of inter-ring haptotropic rearrangements (IRHRs) was investigated by DFT for the tricarbonyl η6-complexes of group 6 metals (M = Cr, Mo, W) of coronene (I-M), kekulene (II-M) and a model graphene (III-M). The computed η6,η6-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 (ΔG# ≈ 20–25 kcal mol−1 vs. ≈ 30 kcal mol−1). The barrier is further lowered in the case of the model graphene complex III-Cr (ΔG# ≈ 13 kcal mol−1). An even lower barrier is found for III-Mo (ΔG# ≈ 10 kcal mol−1), whereas it slightly increases for III-W (ΔG# ≈ 14 kcal mol−1).