Anisotropic thermoelectric power of TTF-TCNQ

We have measured the thermoelectric power along the a-axis as well as the highly conducting b-axis in TTF-TCNQ crystals. Measurements were taken both parallel and perpendicular to the long axis on two sets of crystals. One set grew along the a-axis and the other along the b-axis. The thermopowers are of opposite sign except near 60°K where both cross zero at slightly different temperatures. The a-axis thermopower is consistent with non-metallic diffusive transport in the a direction.     

ESR studies of trans-(CH)x during photoexcitation

A series of spin resonance experiments on samples illuminated with light at photon energies ?ω>E_g are reported. The results set an upper limit on the quantum efficiency for photoproduction of unpaired spins, γ_s? 2×10^-7,implying that the photo-induced excited states and the photo-generated carriers are spinless and are to be associated with charged solitons.