Donor-bridge-acceptor molecules

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... 

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... 

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... 

Davis, W. B. Ratner M.A., and Wasielevski, M.R. (2001) Conformational gating of long distance electron transfer through wire-like bridges in donor-bridge-acceptor molecules, 7. Am. Chem. Soc. 123, 7877-... 

Miller, S. E., Lukas, A. S., Marsh, E., Bushard, P., and Wasielewski, M.R. (2000) Photoinduced charge separation involving an unusual double electron transfer mechanism in a donor-bridge-acceptor molecule, J. Am. Chem. Soc. 122, 7802-7810. 

Wasielewski, MR., Davis, W. B., Miller, S. E., and Ratner, M. A. (2000) Effects of bridge dynamics on electron transfer in donor-bridge-acceptor molecules From photosynthesis to molecular wires, Abstr. Pap. -Am. Chem. Soc. 220th INOR-289. 

Jortner, J. Bixon, M. Wegewijs, B. Verhoeven, J.W Rettschnick, R.P.H. Long-range, photoinduced charge separation in solvent-free donor-bridge-acceptor molecules. Chem. Phys. Letters 1993, 205, 451 55. 

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... 

Ashwell GJ, Chwialkowska A (2006) Controlled alignment of molecular diodes via ionic assembly of cationic donor-(pi-bridge)-acceptor molecules on anionic surfaces. Chem Commun 1404-1406... 

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- ... 

Recently, new insight into detailed mechanisms of photochemical processes in donor-acceptor pairs (DA) has emerged. To study the role of bridge energy levels on electron transfer rates, a series of rod-like donor-bridge-acceptor (D-B-A) molecules in which a 4-aminonaphthalene-l,8-imide (ANI) electron donor is linked to a 1,8 4,5-naphthalenediimide acceptor (NI) via the 1,4 positions on a phenyl bridge was... 

It is assumed throughout this chapter that the relative positions of the donor and acceptor molecules between which an electron is transferred are fixed either within a large molecule or by a molecular bridge in solvents. In this situation, electron-transfer (ET) reactions are governed by first-order kinetics. In second-order reactions [1], the donor and acceptor first diffuse to mutually appropriate positions where the reaction takes place with a position-dependent rate constant. In that case, this is the rate constant discussed in the present article. 

Figure 11.1 Photoinduced electron transfer from molecules to semiconductor nanoparticles, (a) Depiction of a donor-bridge-acceptor system (b) schematic diagram of relevant orbitals.

Also considered was the mechanism for the interchange of the donor and acceptor molecules. As illustrated in Figure 10, the lowest-energy reaction pathway includes a cyclic structure as transition state. The O —H" 0 angle is calculated to be 112° at either the SCF or MP2 level. The two non-bridging hydrogens lie alternately above and below the plane of the two H-bonds, leading to a Q... 

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