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The highly conducting TTF [M(dmit) 2 ] 2 compounds with M= Pd, Ni have been investigated at microwaves. The temperature dependence of real and imaginary part of conductivity was measured from T=77K to 300 K. The Ni salt remains metallic, while the Pd salt reveals at f=2GHz a metal-insulator transition at T p =260K with the negative dielectric constant below T p . The non-linear microwave conductivity of Pd salt was observed in the temperature range 105÷200K, while the Ni salt exhibited the linear conductivity. The results observed can not be accounted for in the framework of known model approach of the collective CDW transport.

It was investigated experimentally the microwave reflectivity of a thin layer of randomly placed highly-anisotropic needle shaped crystals. The unexpectedly high dissipation of microwave energy has been observed. As the anisotropic crystals highly conducting quasi-one-dimensional (1D) crystals have been used.

Low dimensional conductors (LDC) showing a strong anisotropy of crystal structure and electron properties are characterized by the Peierls metal-insulator transition accompanied by charge density wave (CDW) formation. The CDW contribution to conductivity of such conductors results in unusual electric properties: frequency and electric field dependent conductivity, current oscillations, etc. These properties ensure possible practical applications of LDC's in microwave electronics: sensitive bolometers as well as expanded dynamic range mixers and electrically and optically controlled switches. The bulk nonlinear properties of these materials are used, which leads to simple designs, eliminating the need for submicron technique. LDC's exhibit nonconventional electric properties which enables their possible applications in microwave electronics to be discussed. They have an anisotropic crystal structure accompanied by a strong anisotropy of electric properties. Quasi-one-dimensional conductors CID) are characterized by the presence of well conducting stacks of molecules which are weaakly bounded to each other and similar to a system of metallic filaments inserted into a dielectric matrix. In quassi-two-dimensional conductors (92D0) t he highi conductivity exists in a crystallographic plane.