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 fluorinati on reaction using CuF2 as the fluorinating reagent. The oxyfluorides r etain the structures of their precursors, but striking lattice expansi ons are observed. No trace of SrF2 was detected in the fluorinated pro ducts. F doping was successfully used to induce superconductivity in t he 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 Pr1.6 Sr0.4CuO4-xFx.