Low Temperature Infrared Studies of TTF-TCNQ

Abstract
Polarized infrared reflectance measurements have been made on TTF-TCNQ single crystals at temperatures between 25 K and 300 K. Measurements were made for frequencies between 7 cm−1 (1 meV) and 20,000 cm−1 (2.5 eV). These measurements support a charge density wave mechanism for the high dc conductivity of TTF-TCNQ and provide estimates for the 60 K lifetime and the low-temperature pinning frequency of the charge density wave. A value, 300 cm−1 (0.04 eV), for the semiconducting energy gap is also obtained.