Conjugated bridges

As with the oxo-Mov complexes mentioned in the previous section, the NIR transitions become far more impressive when two or more of these chromophores are linked by a conjugated bridging ligand, as in [ Ru(bipy)2 2(/u-L21)]"+ ( = 0-4), which exhibits a five-membered redox chain, with reversible... 

Fig. 8 Projection in the (110) plane of cii-MnII(hfac)2(TTF—CH=CH-py)2 showing alternating layers of organic and inorganic entities linked by conjugated bridge...

The crystal structure consists of TTF layers in the (002) planes which alternate with inorganic Cu(hfac)2 layers in the (001) planes. These two layers are linked by conjugated bridge (Fig. 10a). Figure 10b focuses on the organic plane the TTF units form dimers with the shortest S—S contact equal to 3.593(3) A. In one dimer, each TTF belongs to two different complexes with copper ions lying in two... 

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... 

The length of the conjugating bridge between the terminating heterocyclic donor moieties... 

The electronic characteristics of the individual atoms in the conjugating bridge... 

Fig. 8 Bridge type connecting the donor and acceptor moieties, (a) Insulating bridge, (b) Redox gradient bridge, and (c) highly conjugated bridge...

Fig. 8 Schematics of various linear (one-dimensional) chromophores classified based on the substitution pattern. I-IV quadrupolar molecules V dipolar molecules (D = donor group 7T = 7T-conjugated bridge A = acceptor group)...

The 2PA cross section also increases when the jr-conjugated bridge is extended, as shown for D-tt-D o, o -diphenylpolyenes q.2, q.6-q.9 in Table 1 the value of <5max increases from 2.0 x 10 to 1.3 x 10 GM going from 1 to 5 double bonds in the chain [94]. A red shift in the position of the 2PA peak accompanies the increase in cross section. A similar trend in A ax and 5max is observed when the chain length is increased from q.2 to q.lO and q.l2 by adding phenylene-vinylene units (Table 2). The increase in cross section is... 

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