Mechanisms for the incorporation of a nitrogen atom into polycyclic aromatic hydrocarbon cations

The growth of a second aromatic ring, for cationic species containing a nit rogen atom, is studied at the B3LYP/6-31G* level of theory. For the most fa vorable processes, the maximum barrier is about 15 kcal/mol and is associat ed with the breaking of an aromatic C-H bond. This barrier is similar in ma gnitude to that found for the pure hydrocarbon case. Thus, the inclusion of nitrogen into polycyclic aromatic hydrocarbon (PAH) rings seems favorable if HCN is present during the ring growth processes. (C) 2001 Elsevier Scien ce B.V. All rights reserved.