Functionalization of Carbon Nanotubes with Vaska's Complex: A Theoretical Approach

The functionalization of single-walled carbon nanotubes (CNTs) with Vaska's complex trans-Ir(CO)Br(PPh3)2
has been investigated by means of hybrid quantum mechanics/molecular mechanics (QM/MM) calculations.
The formation of a stable adduct has been experimentally evidenced by Wong et al. (Nano Lett. 2002, 2, 49),
but microscopical details on the metal−nanotube interaction are still unclear. Our calculations show a low
propensity to η2 coordination of Vaska's complex with the perfect hexagonal network of CNTs. Rather, a
stronger interaction takes place when the transition metal center coordinates to carbon atoms belonging to
pentagonal rings, as in topological defects or end-caps.