Graphene intermolecular interactions

Pure PANI exhibits an absorption peak at 334 nm owing to the transition of the benzenoid ring. The band located at 625 nm corresponds to the benzenoid-to-quinoid excitonic transition. On the other hand, the absorption peak of graphene/PANI nanocomposites visible at 330 nm display blueshifts of 4 nm as compared to that of PANT It may be due to the improved intermolecular interaction and very high-energy band gap of the nanocomposites. 

Y.. Dappe, M.A. Basanta, F. Flores, J. Ortega, Weak chemical interaction and van der Waals forces between graphene layers A combined density functional and intermolecular perturbation theory approach, vol. 74, p. 205434-9, 2006. 

This structure also revealed that the fullerene is only partially encapsulated, with an average intermolecular distance of 3.4 A, similar to the interlayer distance in multi-walled carbon nanotubes and multi-layer graphene. From this discovery, Kawase was able to investigate further the dynamics of the [6]CPPA-fullerene interaction [21] and also to synthesize naphthyl- derivatives of CPPAs with deeper cavities and stronger interactions such as 16-18 (Figs. 11 and 12) [22,23] (Table 1). 

Recently, two datasets were developed that contain interaction energies corresponding to complexes of relatively large intermolecular systems. Although no transition metal moieties were presented, the databases are worthy of note as complexes represented in these databases are of the scale comparable to typical graphene-transition metal model systems. 

It is expected that enlarging the aromatic macrocycle would enhance the columnar order due to intense, intermolecular n-n interactions and, thus, increase the charge carrier mobility. Hexa-peri-hexabenzocoronene (HBC) is one of the largest and most symmetrical of all-benzenoid polycyclic aromatic hydrocarbons, that function as a core fragment for DLCs. Hexa-peri-hexabenzocoronene contains 42 carbon atoms and 13 phenyl rings, so it can be considered as a nano-graphene. Mullen... 

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