Noncovalent interaction and its influence on excited-state behavior: A theoretical study on the mixed coaggregates of dicyanonaphthalene and pyrazoline

In the present letter we investigate the noncovalent interactions in the mixed coaggregates of 1,3,5-triphenyl-2-pyrazoline (TPP) and 1,4-dicyanonaphthalene (DCN) and their influence on the excited-state properties of the TPP–DCN. The theoretical results show that the π–π stacking interactions play an important role in the noncovalent interactions of the TPP–DCN coaggregates. The effect of the π–π interactions on the excited-state properties of the TPP–DCN is also fully investigated, and the results indicate that the TPP and DCN do not form an intermolecular charge-transfer complex in the ground state, whereas they form an exciplex in the excited state.