Perylene cores

Coumarin 2 has been paired as a donor with a diamino-substituted per-ylene near-IR emitter to produce a FRET-based UV to NIR frequency converter (Scheme 31) [92]. Excitation at the coumarin 2 A,max ( ex = 345 nm) resulted in FRET to the higher excited state (S ) of the perylene core. This state imdergoes rapid internal conversion to the first excited singlet state (Si, Kasha s rule), from which emission is observed. Comparison of the integrated donor emission in the absence of the core and in the target dendrimer indicated a 99% energy transfer efficiency, accompanied by a 6.2-fold increase in the core emission relative to the emission in the absence of peripheral donors. 

On a fundamental level, these results demonstrate the behavior of extremely small amounts of Ir and Ru at very positive potentials in a PEM envirOTunent The nature of these extraordinary OER activities needs further elucidatimi both from a practical and fundamental point of view. The thin film morphology could be one of the main factors affecting activity, first of all through the favorable surface to mass ratio and further due to the discontinuous nature of the thinner coatings. Finally, the observed interactions with the substrate and the NSTF perylene core could have an effect both on the activity and stability of the OER catalyst. 

First dendritic energy transfer system was published by Balzani et al. in 1992, which was composed of complexes of ruthenium and osmium. Following this, first unidirectional energy transfer from the phenyl acetylene superficial units to the perylene core was reported by Xu and Moore Dendritic benzyl ether ligands coordinated to the... 

Fig. 2 Multichromophoric molecular squares 8a-c and molecular model of perylene-walled light-harvesting molecular square 8a. In model the phosphane ligand is replaced by an ethylenediamine chelate ligand for simplicity. In squares 8a-c a p-carbonyl-oxyphenoxy unit is used as the spacer between the perylene core and antenna dye linkage...

The main sensing material/transducer consists of building blocks of conducting polymer (based on perylene core molecule) coated on nanofibres. Because the core molecule is the CP they were directly coated onto interdigitated electrodes to form an electrical circuit. Due to the inherent redox nature of CP [104, 105] the transducer is sensitive especially to redox active explosives, pesticides and other chemicals including amines, nitros, peroxides, ammonia, phenols and phosphines. Another similar electrochemical devices based on nanofibres were created by Nottingham Trent University and Nano products ltd (UK). 

The polyphenylene dendrimers were fbimd to effectively isolate large chromophores such as perylene derivatives, when two polyphenylene dendrons (first through third generation) are attached to a perylenediimide core (PDl) (Scheme 34) [95]. Although the alkoxy substituents in the bay area of the perylene twist the core out of planarity, the chromophore is only shghtly blue-shifted when incorporated into the dendrimers. Therefore, energy transfer from the polyphenylene dendrons is still accomphshed with high efficiency. 

Takahashi et al. [105] reported a family of dendrimers with perylene tetracarboxylate cores and layers of 4, 8, 12, 16, or 24 anthracene imits at-... 

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