TRANSPORT-PROPERTIES OF CU-O CHAINS IN SR2CUO3+DELTA

High-pressure oxidation of Sr2CuO3+delta With delta<0.1 has produced s amples with metallic chains as well as those with small-polaron behavi or. The paramagnetic susceptibility evolves with increasing delta from a primarily Bonner-Fisher temperature dependence to a Curie-Weiss beh avior for small-polaron samples and a strongly mass-enhanced Pauli par amagnetism for the metallic samples. Samples of intermediate oxidation exhibited a smooth transition from metallic behavior at low temperatu res to small-polaron behavior at higher temperatures. The small low-te mperature Seebeck coefficient alpha(T) of the metallic samples exhibit ed 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 as sociated 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)app roximate to 140 K found for the chains in YBa2Cu3O6.96 is the result o f a strong elastic coupling to the superconductive CuO2 sheets and is not an intrinsic property of the chains.