Influence of fluorination treatment on the structural and superconducting properties of La(sub 2-x) Ba(sub x) CuO(sub 4) compounds (x=0.08, 0.125 and 0.15)

摘要

The fluorination treatment at 200 C of La(sub 2-x) Ba(sub x) CuO(sub 4) compounds with x= 0.08, 0.125 and 0.15 leads to superconducting materials having a same critical temperature of Tc about 32 K. The investigation of these compounds by neutron powder diffraction shows that the halogenation process drastically modifies their structural properties. Particularly, it is observed a decrease of the orthorhombic distortion in the LTO-phase (x = 0.08 and 0.125) and a reduction of the tilt angle of the (CuO(sub 6)) octahedra in the LTT-phase (x 0.125). (authors). 3 refs., 1 fig. (Atomindex citation 28:016887)