Supramolecular fullerene/porphyrin charge transfer interaction studied by absorption spectrophotometric method

Photophysical and theoretical insights on non-covalently linked fullerene–zinc phthalocyanine complexes

“…Table 2. It is already well established that in fullerene-porphyrin complexes, the 6:6 ring-juncture bond of the C 70 , rather than 6:5 ring-juncture bond, lies closest to the porphyrin plane [72][73][74] as the 6:6 "double" bonds of C 70 are more electron-rich than 6:5 "single" bonds. Thus, in our present work, the equatorial face of C 70 is centered over the electropositive center of the ZnPc plane which may be viewed as a spontaneous enhancement in van der Waals interaction due to availability of greater amount of volume (V) and surface area (A) favoring strong -interactions.…”

Photophysical investigations and binding strength in supramolecular interaction of a newly designed diporphyrin tweezer with fullerenes C60 and C70 in solution

“…The most important feature of all these structures is their unexpectedly close contact between fullerene and 1. As shown in Figure 4a, C 70 is alligned within the cavity of 1 in side-on orientation which allows the p-rich region of C 70 , i.e., 6:6 ring-juncture at equivalent position, to maintain very close distance with the plane of the porphyrin for creating fruitful interaction [32]. The distance between the Zn2 number atom of 1 and C76 number carbon atom of C 70 is computed to be 3.201 Å.…”

van der Waals interactions are critical in Car–Parrinello molecular dynamics simulations of porphyrin–fullerene dyads

“…This is supported by binding constants as large as 10 5 M −1 and by classical MD studies with various force fields which estimated the vdW contribution to account for (80–95)% of the interaction, the rest being electrostatic. However, C 60 has a high electron affinity and rather high polarizability which are claimed to favor not only intermolecular interaction but also electron density redistribution . It is therefore proposed, based mainly on spectroscopic investigations, that the π–π interaction in Ph–C 60 systems involves some nonnegligible degree of electrostatic attraction or charge transfer (CT) .…”

“…However, C 60 has a high electron affinity and rather high polarizability which are claimed to favor not only intermolecular interaction but also electron density redistribution . It is therefore proposed, based mainly on spectroscopic investigations, that the π–π interaction in Ph–C 60 systems involves some nonnegligible degree of electrostatic attraction or charge transfer (CT) . Imahori et al reported such interaction in dyads in which C 60 and Ph were closely linked to each other.…”