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The aim of this work is to understand the molecular structural properties which may justify the great observed stability of doped alkoxy polythiophenes. Infrared frequency and intensity spectroscopy and Raman spectroscopy are used as probes. Suitably synthesized oligomers with increasing chain length and preassigned chemical structure have been studied together with several model molecules. The existence of through-space and through-bond S- - -O interactions has been revealed. The extent of the topologically dependent perturbation induced by the charge injection by the oxygen atoms is detected and measured. The inter- and intraring delocalizations have been monitored by the observation of the softening of the strongly Raman active ‘‘amplitude mode’’ and by the red shift of the electronic spectra. The conformation of the side chains is trans planar in the solid state and collapses in a liquidlike premelting state before the melting of the crystal.

The technique of small angle neutron scattering (SANS) is ideally suited for determining the length scale of magnetic correlations in nanocrystalline materials. The additional use of polarized neutrons also allows for a clear separation between magnetic and non-magnetic scattering. The temperature dependence of the SANS cross-section from a two-phase alloy, consisting of both amorphous and nano-crystalline parts, Fe 89 Zr 7 B 3 Ctu,, has been measured in the temperature range from 293 to 500 K. The SANS measurements are accompanied by bulk magnetization and Mbssbauer transmission data. In this range of temperatures, the magnetic contrast between the nanocrystalline and amorphous phases, which are both magnetic, changes dramatically. This phase contrast increases up to 380 K, which is the proposed decoupling temperature for the inter-granular exchange stiffness. Above this temperature, the contrast levels off slowly, being totally dominated by the decreasing magnetization of the nanocrystalline phase.

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