Electron donor and acceptor sites

Intramolecular reactions of electron donor and acceptor sites in cyclic starting materials produce spirocyclic, fused, or bridged polycyclic compounds. 

A theoretical formalism is available for understanding optical charge transfer processes in a variety of chemical systems (mixed-valence ions, donor-acceptor complexes, metal-ligand charge transfer chromophores, etc) where the extent of charge transfer is large and where electronic coupling between the electron donor and acceptor sites is relatively small. 

A second test involves the role of internuclear separation between the electron donor and acceptor sites. Rearrangement of eq 8 leads to the prediction of a -1/d dependence for E. ... 

The existence of interdependent electron-donor and -acceptor sites on various surfaces has been demonstrated by Flockhart and co-workers (57, 38,332,335). These authors have shown that the spin concentrations of perylene are increased on surfaces that are precovered with TNB, and vice versa. Up to tenfold enhancement of the reducing activity of a zeolite sample was observed when electron-donor molecules are preadsorbed on the surface (38). These results... 

The simplest component of an electrical circuit is a wire, and the design of molecular wires has received a great deal of attention. In a broad sense, this term can be used to designate any molecular" structme able to mediate the transfer of electrons between appropriate electron donor and acceptor sites (electrodes, photoactive, and redox-active molecular components). In practice, different "conduction mechanisms may apply, depending on the molecular structure of the wire and on the type of experimental setup used (see below). Molecular wires were studied in a variety of experimental conditions, depending on the nature of the donor and acceptor terminals the wire is connected to. and on the method used to detect the electron flow. Available methods can be broadly divided into the following (Fig. 1) photoinduced eiectron transfer in donor-wire-acceptor systems (dyads), fast electrochemistry of adsorbed wire-electroactive group assemblies, and conductance [/(V)] measurements on metal-wire-metal junctions. 

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