The electrical conductivity of TTF-TCNQ under pressure

Abstract

We report b-axis electrical conductivity data for TTF-TCNQ single crystals from 20-300 K under hydrostatic pressures of up to 6 kbar. There are two anomalies in the conductivity. Under pressure, the temperature of the well-known metal-insulator transition at 54 K increases slightly (in agreement with the earlier work of Chu et al.). We find that the temperature of the lower anomaly at 38 K decreases slowly with pressure. Since there is evidence that the conduction electron bandwidths increase substantially in the above pressure range it is not easy to interpret these results in terms of current theories of the Peierls transition