The influence of fluorine on the structures and properties of Pr2-xSrxCuO4-y (x=0.0, 0.4, 1.0)

Introducing F into the lattices of the copper oxides Pr2CuO4, Pr1.6Sr0.4CuO4 and PrSrCuO4-y is accomplished via a low-temperature fluorination reaction using CuF2 as the fluorinating reagent. The oxyfluorides retain the structures of their precursors, but striking lattice expansions are observed. No trace of SrF2 was detected in the fluorinated products. F doping was successfully used to induce superconductivity in the oxyfluoride PrSrCu(O, F)(4-delta) (T-c = 15 K) with a reduced CuO2 plane and in the presence of apical anions, but failed to optimize the carrier density and induce superconductivity in Pr2CuO4-xFx and Pr1.6Sr0.4CuO4-xFx.