Conducting polymers magnetic susceptibility

Poly(sulfazene) forms single crystals, that is, bundles of highly oriented fibers. The polymer behaves as a metal with respect to reflection, specific heat capacity, electrical conductivity, and magnetic susceptibility. The specific resistance is about 0.001 H cm at room temperature. The polymer is superconducting at 0.26 K. 

The charged quasiparticles can be probed by electrical dc conductivity measurements (for polarons), magnetic susceptibility (for polarons and bipolarons), electron-spin resonance (ESR) (for polarons) and optical measurements (for polarons and bipolarons). As ESR is well suited for studying spin-carrying polarons, optical modification of the ESR (optically detected magnetic resonance ODMR) can be applied to link the emissive or absorbing properties of the polymer with its spin state. 

Initially polymeric KC and RbC o were thought to be isostructural. Indeed, the lattice parameters of the three AC o polymers with A=K, Rb, Cs are similar [58]. However, the strong dilferences in the physical properties, in particular the magnetic susceptibilities, electrical conductivities [10] and MAS spectra [59] indicated some undetected structural differences. Brouet et al. [60] suggested from an analysis of MAS spectra that the main difference is in the relative orientation of neighboring C<,o chains. The MAS spectrum shifts are determined in principle both by inter and intra fullerene interactions and are sensitive to small structural differences. Some of the 16 inequivalent C lines of the polymer are well resolved and it was found that the C MAS spectra of polymeric RbCgo and CsCgo on the one hand, and polymeric KC o on the other, are very different (Fig. 13). 

Whatever the precise mechanisms of conduction, the macroscopic conductivity observed in any conducting polymer will depend strongly on the morphology of the sample and on whether it is oriented and, if so, to what degree, because these factors will influence both intra- and inter-chain mobility. For these reasons the conductivities of samples prepared under very similar conditions may differ considerably. The above account has merely attempted to indicate some of the types of process that may be involved in conduction in these relatively new materials, for which it is certain that no single mechanism can explain all the experimental results. Even when a particular theoretical description fits the conductivity, it cannot be accepted as the correct mechanism unless it can also accoimt for the observations of magnetic susceptibility, thermo-electric power, photoconductivity and other properties. 

Poly(CuPc) Poly(CoPc) Poly(NiPc) Sheet polymers of metal phthalocyanines insoluble electronic spectra, magnetic susceptibility, electrical conductivity, x ray diffraction discussed. [168]... 

The inertness of polymers could prove very beneficial if they possessed certain bulk properties such as electrical or magnetic susceptibility that one could exploit. We believe that the electroactive polymers, namely electronically and ionically conducting polymers, piezoelectrics, and electrets, by virtue of their susceptibility to either mechanical or electromagnetic or thermal or optical phenomena, could be utilized to interface between the external world and the physiological environment and could prove quite beneficial in eliciting the desired cellular response. These polymers represents a new modality in the development of interactive scaffolds for tissue stimulation, tissue regeneration, and the development of bioartificial organs. 

The presented results show that for magnetic polymer composite films it is observed also dependences similar to those ones for conducting polymer composites, because frequency is reduced when magnetic particle concentration and, consequently, local susceptibility and inductance increases. 

Metallic properties of doped conjugated polymers are observed in the temperature dependence of conductivity, magnetoresistance, thermopower, magnetic susceptibility, and infrared reflectivity. However, the materials of this class are not yet really metallic with long mean free paths they remain just on the metallic side of disorder-induced M-I transition. This implies that significantly higher electrical conductivities will be obtained with continued improvement of the materials. 

Rosenblum and cowoikers have described a number of routes to lace-to-lace polymetallocenes. Ruthenium- and iron-based materials were synthesized via palladium-catalyzed cross-coupling reaction of 1,8-diiodonaphthalene with metallo-cenylzinc chloride (M=Fe, Ru). The MW of the face-to-lace polyferrocenes with R=H,R = 2-octylwasintherangeof 18,000, while that of200 when R=R =2-octyl, was 139,000. The conductivity of polymer 200 (M=Fe, R=H, R =2-octyl) on doping with I2 was 6.7 X 10 S/cm. The incorporation of nickelocene and cobaltocene units into the fece-to-lace polyferrocenes resulted in materials with magnetic susceptibilities of 3.51 and 5.2 (1 for the Ni Fe and Co Fe ohgomers, respectively. ... 

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