Porphyrin stacking

FIGURE 7.26. (a) Molecular structure of compounds 42—45 (b) TEM images of a bundle of nanorods formed by compound 43 (Upper), and closer view of the bundle (Lower), (c) Pictorial representation of the nanorods formed by self-assembly of salt 43 in water, (d) Nanotubules formed by compound 45 observed at different scales. The measures of the two focused tubules are 35 x 530 and 50 x 470 nm. (e) Most stable dimeric structures of 45. Note that Upper is 6 kcal/mol per molecule more stable than Lower. (Upper) Interlayered structure (see text). (Lower) Porphyrin stacked structure. Notice that the porphyrin stacked structure is 2 kcal/mol per molecule more stable than the interlayered structure. 

Figure 6.3.1 Absorption spectra of the covalent porphyrin stacked and lateral pen-tamers shown in Scheme 6.3.3. Stacks show only short-wavelength shifts lateral assemblies often give, although not in the present case, both short- and long-wavelength Soret bands.

Figure 6.8.2 Typical configuration of amphiphilic porphyrin stacks on a water surface. (From Schick et al., 1989.)...

Figure 3. Schematic representation of the coiumnar arrangement of discotic zinc rr-decyl ether octa-substituted porphyrin stacks. Reprinted with permission from Liu, C, Y. Pan, H. L Tang, H. Fox, M. A. Bard, A. J. /. Phys. Chem. 1995, 99, 7632 1995 American Chemical Society,...

The modified electrode with the attached CoTPP can reduce CO2 to CO whereas the electrode modified with adsorbed CoTPP cannot. The cyclic voltam-mogram of the modified porphyrin-amine-GC electrode in pH 6.8 phosphate buffer shows the appearance of the anodic hump after the electrode is polarized to potentials where the evolution of hydrogen takes place under N2 atmosphere see Figure 5.12. The ligand bonded to the glassy carbon does not show this hump, and then the authors associate it with the cobalt center. The hump would correspond to the oxidation of the formed hydride. Over the first-bonded porphyrin there are more than 100 layers of stacked porphyrins. Stacked Co(II)TPP could accept a hydrogen atom from CoTPP bonded GC to form HCo(II)TAPP. ... 

Recently, an example of an efficient BHJ SC was assembled of commercially available components by careful D-A interface optimization (Table 30) [108, 109]. Here, self-assembled porphyrins stacks were used as the charge mediators to assist effective exciton dissociation at the photocathode. This approach allowed con-stmcting BHJ SC with the PCE as high as 7.13 %. 

The stacked porphyrin arrays assembled on DNA templates are reminiscent of the columnar liquid crystalline (LC) phases produced by discotic mesogens, including several porphyrin derivatives [67]. Different discotic compounds with complementary interactions have been shown to form mixed LC phases [68], a concept that has been extended to the DNA-templated porphyrin stacks [69]. The two porphyrins Hj-P4... 

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