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We show that the newly discovered phase transitions in (TMTTF)2X (X=PF6, AsF6, SbF6, ReO4) are characterised by a huge divergent peak in the low frequency dielectric constant. These phase transitions can be explained by combined effect of charge disproportionation on TMTTF molecules and the uniform shift of anions, yielding thus a macroscopic ferroelectric polarisation. Anion ordering transition, which occurs for non-centrosymmetrical anions, has a specific effect depending on the distortion vector: it destabilises the ferroelectric state in the (TMTTF)2ReO4 and brings an antiferroelectric character to the transition in (TMTTF)2SCN.

The spatial distribution of electric field E between two current terminals to quasi-one-dimensional conductor TaS 3 has been studied using the multicontact configuration. In the low temperature range (30–50 K) at low voltage V between current terminals we observed strong increase of E near negative terminal, while near the positive terminal we observed the lowering of E. The observed asymmetry of the spatial distribution of E is supposed to be related to the formation of two Schottky barriers on the metal-Peierls semiconductor contacts which are biased one in reverse and another in forward directions.

We have measured the conductivity of orthorhombic and monoclinic TaS 3 as well as blue bronze K 0.3 MoO 3 as a function of electric field (10 −2 V/cm to 500 V/cm) at the low temperature down to 4.2 K. Two threshold fields E T ′ and E T are revealed and their temperature dependences are analyzed. The results obtained are explained on the base of supposition that the onset of non-linear conductivity is associated with the beginning of the motion of defects and dislocations in CDW superlattice. At the electric field range E T ′ T this motion has random character, but at E>E T the slippage of CDW phase with periodical nucleation and coherent motion of these dislocations becomes main process.

Polarized infrared reflectance and transmittance spectra have been measured on NbS3 crystals with two-fold commensurate superstructure (type I) which is in a sense similar to polyacetylene. From these data spectra of absorption coefficient at the temperatures 300 and 8.5 K have been calculated. It was shown that the absorption in the spectral range v >6700 cm−1 is provided by electron-hole excitations across the Peierls gap. In the energy range v

We prepared conducting Langmuir-Blodgett (LB) films of charge-transfer complexes using (C 16 H 33 -TCNQ) 1−x (C 17 H 35 -DMTTF) x mixture and measured conductivity in a wide temperature range and Hall constant at the room temperature. Electron microscopy and electron diffraction technique were used to make more clear the causes of some peculiarities of temperature dependencies of conductivity.

High spatial resolution (30–100 μm) X-ray measurements of the satellite positional shift q have been carried out in the upper charge-density-wave state of NbSe 3 . We determined the spatial distribution of the CDW plastic deformations between electrodes under applied currents. With direct current we observe a steep exponential decrease of q with position x along the sample near the contacts followed by a linear dependence in the central part of the sample. This second regime is attributed to transverse pinning of the CDW dislocations while the first is dominated by phase slip processes. The observed differences between data from direct current and pulsed current measurements indicate a significant, strongly spatially dependent relaxational behaviour of the CDW deformations.

Bolometric spectra of orthorhombic TaS 3 have been measured in the range of the fundamental absorption edge. The transition from the pseudogap to the fairly pronounced Peierls gap in the electronic spectrum was observed with decreasing temperature. However, the absorption edge remains broadened by the order of value of the gap. The results are in the qualitative agreement with the appropriate theories.