Cation-Radical Salt structure

The insulating oligomers were reacted with iodine to create a new, cation-radical salt structure of high conductivity. The crystal structure of the iodine complex of N,N -diphenyl-p-phenylene diamine (PPAa)cI> 2 partially resolved by Huml and... 

Cerrada, E., Laguna, M., Bartolome, J., Campo, J., Orera, V. and Jones, P.G. (1998) Cation-radical salts with organometallic gold anions. X-ray structure of TTFPh]2[Au(C6F5)2]. Synthetic Metals, 92(3), 245—251. 

Matsubayashi et al. revealed donor abilities of the unsymmetrical diimine-dithiolene complexes [11-14]. The unsymmetrical complexes provided cation radical salts with various anions including I3, Br3 and TCNQ by use of chemical oxidation [11-14]. The electrical resistivities of the cation radical salts measured with their compressed pellets at room temperature are summarized in Table 1. The electrical resistivities of the dmit complexes were very high. The cation radical salts of the CgH4Sg-complexes, which have the BEDT-TTF moiety [22, 23], exhibited lower resistivity than those of dmit complexes, except for [(Bu-pia)Pt(CgH4Sg)] salts. However, crystal structures of these salts were not reported, and details of their electrical properties and electronic states were not discussed based on their crystal structures. 

Crystal Structure of the Cation Radical Salt [(bpy)Pt(C8H4S8)][BF4]... 

Crystal structure data are indispensable for the discussion of the conduction mechanism in the cation radical salts based on the unsymmetrical complexes. In 2002,... 

Energy Band Structures of the Cation Radical Salts [(ppy)Au(S-S)]2[anion] (S-S = CgH4Sg or CgH4S602, anion =PFfi or BF4 )... 

One-dimensional stacking of the molecules may provide a framework for possible band structure formation. In this case, repeat units should preferably have an overall planar geometry. This concept can be extended to two-dimensional (2D) structural arrangements where interactions between the molecules are found along two directions as in cation-radical salts derived from TTF-like molecules such as BEDT-TTF (BEDT-TTF = C10H8S8, bis(ethylenedithio)-tetrathiafulvalene) (13), or even to three-dimensional (3D) systems such as the doped A Ceo fullerides (47). 

The second family of superconducting materials is based on cation-radical salts of another donor, bis(ethylenedithio)-TTF (abbreviated BEDT-TTF or ET), which exhibit two-dimensional network mostly due to inter-stack S S interactions [100]. Another important feature of BEDT-TTF salts is their tendency to give polymorphs. For instance, (BEDT-TTF)2I3 salt affords four polymorphs (a, p, 0, and k phases), of which only the first undergoes metal-insulator transition, while the others are superconductors at ambient pressure (see Chapter 10 of this book). It is quite surprising that of all numerous BEDT-TTF structural analogs synthesized to date, only two salts of unsymmetrical derivatives, DMET [101] and MDT-TTF [102], led to superconductors. 

TTFs, also named 2,2 -bi-l,3-dithiole, 2,2 -bi-(l,3-dithiolylidene), are one of the most studied systems in the field of molecular materials because of their ability to participate in electrically conducting and superconducting cation radical salts or CT complexes. The utility of TTF derivatives as building blocks in macromolecular and super-molecular structures, molecular-based ferromagnetic compounds, donor moieties in intramolecular D-A systems in... 

X-Ray crystal structure analyses of neutral 3,4-dimethylanthra[l,9-rz/ 4,10-4r/ ]bis-l,2-ditellurole 9 and its cation radical salts with several anions have been performed <1997CC593, 2005EJI3435>. Crystal structures of 3-(SCN)o.8s> 3-(C104)o,88 3-(AsF6)o,7, 3 Ag(CN)2, and 3 Au(CN)2 were reported <1998IC2850, 2005EJI3435>. 

K. Takahashi, T. Ise, T. Mori, H. Mori and S. Tanaka, Synthesis of BEDT-BDTBS and crystal structures of its conducting cation radical salts, Chem. Lett., 1001-1002 (1996). 

Fig. 1. The crystal structure of neutral naphthalene (A) and of the cation-radical salt (naphthalene)2 5 (B).

Fig. 2. Projection of the crystal structure o the fluoranthene cation radical salt FA 2 6 at 298 K (a) onto the b,c-plane (b) normal to the stack axes. Data cf. V. Enkel-mann et al. ...

Fig. 4. Structure of the cation-radical salt of N,N-di-pheny1-p-pheny-lene diamine with I -counterions (black dots) hydrogen bonds are indicated by dotted lines cf. ref. 22.

In a series of papers these authors described the preparation, structure and electronic behaviour of a series of cation-radical salts of oligomeric poly(p-phenylene amine)s (PPA) of the general formula. 

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