Distinct host-guest interaction and subdued fluorescence in a coordination network of 2,3,6,7,10,11-hexakis(phenylthio)triphenylene and silver(I) triflate

This paper reports our recent efforts in using host-guest interactions to control the fluorescent properties of coordination networks containing polycyclic aromatic units. The polycyclic aromatic ligand 2,3,6,7,10,11-hexakis(phenylthio)triphenylene (HPhTT) coordinates with AgTf (Tf: trifluoromethanesulfonate) in nitrobenzene to form single crystals of a 2-D host network consisting of octameric (i.e., containing eight AgTf units) and dimeric AgTf moieties linked to the HPhTT molecules through the Ag-thioether coordination bonds. The HPhTT adopts a starburst and rather irregular conformation, which apparently contributes to the formation of empty space between the 2-D coordination networks. Such voids are occupied by the nitrobenzene guest molecules, resulting in distinct aromatic-aromatic stacking interactions with the triphenylene units (interplanar distances: 3.46 and 3.60 Å). In comparison to a previous Ag-HPhTT network with toluene as weaker-interacting guests, the current system shows a significantly suppressed fluorescent emission from the triphenylene core, apparently due to the quenching effect from the nitrobenzene guests. © 2006 Elsevier Inc. All rights reserved.