Transport properties of Cu-O chains in Sr2CuO3+delta

High-pressure oxidation of Sr2CuO3+delta With delta<0.1 has produced samples with metallic chains as well as those with small-polaron behavior. The paramagnetic susceptibility evolves with increasing delta from a primarily Bonner-Fisher temperature dependence to a Curie-Weiss behavior for small-polaron samples and a strongly mass-enhanced Pauli paramagnetism for the metallic samples. Samples of intermediate oxidation exhibited a smooth transition from metallic behavior at low temperatures to small-polaron behavior at higher temperatures. The small low-temperature Seebeck coefficient alpha(T) of the metallic samples exhibited a negative enhancement characterized by a hump at approximately 75 K typical of acoustic-phonon drag; there was no evidence for an alpha(T) like that of the CuO2 planes of the superconductive cuprates, which have an enhancement with a T(max)approximate to 140 K that we have associated with vibronic states derived from dynamic pseudo-Jahn-Teller deformations tions of the Cu sites inside large correlation polarons. These data support the suggestion that an enhancement with a T(max)approximate to 140 K found for the chains in YBa2Cu3O6.96 is the result of a strong elastic coupling to the superconductive CuO2 sheets and is not an intrinsic property of the chains.