At low pressure and at a commensurability of 3 (at ∼19 kbar) the low-temperature thermopower of TTF-TCNQ is large, negative, and varying ∼1T. At 17 kbar it is smaller, positive, and independent of temperature. At 22 kbar it is similar to that at 17 kbar but of opposite sign. For P19 kbar pulling of the distortion wave vector from 2kF to a commensurate value (b*3) leaves the TCNQ valence band underfilled and TTF valence band overfilled. For P19 kbar the reverse holds. We suggest that the excess carriers are charged solitons or polarons.
ASJC Scopus subject areas
- Physics and Astronomy(all)