Donor-bridge

Figure C 1.2.10. Representative examples of fullerene based donor-bridge-acceptor dyads and triads.

Guldi D M, Maggini M, Scorrano G and Prato M 1997 Intramolecular electron transfer in fullerene/ferrocene based donor-bridge-acceptor dyads J. Am. Chem. See. 119 974-80... 

Copper(I) halide supramolecular networks linked by N-heterocyclic donor bridging ligands 98PAC2351. 

Wiberg J, Guo L, Pettersson K et al (2007) Charge recombination versus charge separation in donor-bridge-acceptor systems. J Am Chem Soc 129 155-163... 

Hayes RT, Wasielewski MR, Gosztola D (2000) Ultrafast photoswitched charge transmission through the bridge molecule in a donor-bridge-acceptor system. J Am Chem Soc 122 5563-5567... 

Chen KY, Hsieh CC, Cheng YM et al (2006) Tuning excited state electron transfer from an adiabatic to nonadiabatic type in donor-bridge-acceptor systems and the associated energy-transfer process. J Phys Chem A 110 12136-12144... 

Napper AM, Head NJ, Oliver AM et al (2002) Use of U-shaped donor-bridge-acceptor molecules to study electron tunneling through nonbonded contacts. J Am Chem Soc 124 10171-10181... 

Paddon-Row MN (2003) Superexchange-mediated charge separation and charge recombination in covalently linked donor-bridge-acceptor systems. Aust J Chem 56 729-748... 

Ricks AB, Solomon GC, Colvin MT, Scott AM, Chen K, Ratner MA, Wasielewski MR (2010) Controlling electron transfer in donor-bridge-acceptor molecules using cross-conjugated bridges. J Am Chem Soc 132 15427... 

Donor-bridged bis(silylene) complexes (Equation (4)) are now known for all the group 6 metals.72-74 For example, when CpCr(CO)3 is photolyzed with HSiMe2SiMe2OMe, the product is 26 (M = Cr X = OMe). Structural data for members of this family show that the four-membered ring is folded (internal dihedral angle for 26 with M=Cr, X = OMe is 162.4°), and this is attributed to steric repulsion between CO and silicon-bound Me groups. The fluxional... 

When the emissive state is a charge transfer state that is not attainable by direct excitation (e.g. which results from electron transfer in a donor-bridge-acceptor molecule see example at the end of the next section), the theories described above cannot be applied because the absorption spectrum of the charge transfer state is not known. Weller s theory for exciplexes is then more appropriate and only deals with the shift of the fluorescence spectrum, which is given by... 

Some bichromophoric systems, whose structure is based on the donor-bridge-acceptor principle, can undergo complete charge transfer, i.e. electron transfer. The resulting huge dipole moment in the excited state explains the very high sensitivity to solvent polarity of such molecules. An example is FP (l-phenyl-4-[(4-cyano-l- ... 

There are two qualitative ways to influence Hda- One is to modify the V elements. The V elements are changed by altering the donor-bridge and acceptor-bridge interactions. Pulling D and A away from the helix, for example, weakens the V elements. In DNA, if r-orbital-mediated coupling dominated. 

Figure 1. Typical donor-bridge-acceptor system.

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