Perylene-iodine complexes

The first report of a perylene-iodine complex with metallic conductivity was Per(l2)4 by Kao et al. [10], with values as high as 51.9 S/cm at 300 K. A broad maximum of conductivity exists at ca. 235 K (Figure 2.3). In a few samples that did not crack at lower temperatures, a gap of 0.1 eV was measured. The EPR linewidth at room temperature is 10.9 G, clearly distinguishable from the Per2(l2)3 complex. The authors indicate that spin density from EPR exhibits an activated behaviour with = 0.02 eV in the range 100-300 K, consistent with a model of a narrow band-gap semiconductor. The determination of the crystalline structure was not accomplished, but from X-ray oscillation photographs, an incommensurate structure was proposed. 

The use of the tetrachalcogenoperylene molecules such as TTP to obtain molecular conductors has been greatly limited by the low solubility of these compounds, which is much smaller than perylene in the usual solvents. Hilti et al. [120] obtained, by cosublimation of this donor and iodine, a highly conducting compound, TTP-I. 28- In this case, as opposed to the perylene—iodine complexes, the iodine composition was found to be much more stable in a... 

Comparatively little work on copper batteries has been reported. The substitution of silver by copper in RbAg I does not exceed 0.34 wt % and cells of/this electrolyte with copper anodes behaved in an unstable fashion. Preliminary cell measurements have also been reported using NN dimethyl triethylene-d gj ne dibromide - cuprous bromide in conjunction with copper anodes. With charge transfer complex cathodes (Br -perylene, iodine-perylene) the cells were unstable as the halogen oxidised the CuBr (or Cul) reaction product to the Cu state. With a stable behaviour was observed. 

In the above radical-cation salts, the crystal contains partially oxidized donors, while the electroneutrality is achieved by the presence of closed shell anions. The structural requirements necessary for electrical conductivity in solid salts can also be met upon mixing of donors and acceptors in the resulting charge-transfer (CT) complexes both the donor and acceptor exist in a partially oxidized and reduced state, respectively. Famous examples are the conducting CT complexes formed upon mixing of perylene (112) [323. 324] and iodine or of tetrathiafulvalene (TTF, 119) as donor and 7,7,8,8-tetracyanoquinodimethane (TCNQ, 120) as acceptor [325-327] the crucial structural finding for the... 

Use of iodine-silver perchlorate may accomplish cation-radical formation before the oxidizing pair can themselves react. In modern usage, silver ion (as the perchlorate usually) is added to a solution of the substrate and iodine, and the complexity of the iodine-silver perchlorate system is avoided, provided that the substrate undergoes reasonably fast oxidation. Such is the case with perylene (Sato et al., 1969 Ristagno and Shine, 1971) and pheno-thiazine, but not the case with diphenylanthracene and thianthrene (Shine et al., 1972). 

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