We have obtained three-component systems: the complexes comprising of two different benzenoid hydrocarbons together with one molecule of 7,7,8,8-tetracyanoquinodimethane (TCNQ). The X-ray single-crystal structures of naphthalene–perylene–TCNQ and pyrene–perylene–TCNQ revealed that they form face-to-face stacking between perylene and TCNQ molecules containing another hydrocarbon as a guest in the structure. We also present a pyrene–TCNQ complex with two pyrene moieties acting in similar way. In this system, charge transfer is far more efficient than in any other complexes of TCNQ with benzenoid hydrocarbons. Additionally, we have also obtained as references pyrene–TCNQ, chrysene–TCNQ, phenanthrene–TCNQ and naphthalene–TCNQ with 1 : 1 molecular ratios. These systems were also used to estimate the degrees of charge transfer.

Application of topological properties and graph theory to benzenoid hydrocarbons allowed us to construct an effective approach interpreting ring current formation in molecules when exposed to an external magnetic field. Transformation of unexcited canonical structures for molecules of 34 benzenoid hydrocarbons into circuit structures and then to directed circuit structures allowed us to define global magnetic characteristics (GMC). GMC/n² values correlate very well with exaltation of magnetic susceptibility ΔΛ/n² (computed at the CSGT/B3LYP/6-311G** level of theory by using optimized geometries at the B3LYP/6-311G** DFT level) with cc = 0.993. If the approach is applied to individual rings, then the correlation between local magnetic characteristics (LMC) for 129 various rings of 34 benzenoid hydrocarbons and NICS(1) works with cc = −0.975.