Structural peculiarities of two layered cuprates, NdSrCuO3.5 and Nd1.8Sr1.2Cu2O6−δ

Structural and electrical changes in NdSrNiO4−δ by substitute nickel with copper

“…The unit cell parameters for the end members (x ¼ 0 and 1) agree well with those reported in the literature [14,22]. A final fit for NdSrNi 0.8 Cu 0.2 O 4Àd is displayed in Fig.…”

Synthesis and characterization of La0.8Sr1.2Co0.5M0.5O4−δ (M=Fe, Mn)

“…The oxide ion vacancies created in these materials are confined to the equatorial planes of the K 2 NiF 4 -type structure. Attempts to refine a model in which oxide ion vacancies were distributed between axial and equatorial positions in a manner similar to NdSrCuO 3.56 [8] proved unstable. A displacement of equatorial oxygens (O1) in the xy plane was also observed, which transforms the oxide ion at (0.5,0,0) to the split position (0.5,y,0).…”

“…8 for 12 h at 700 and 1000°C, respectively. X-ray powder diffraction (XRD) data were collected using a Siemens D5000 diffractometer in transmission mode, employing CuKĮ 1 radiation from a germanium monochromator.…”

Structural and Magnetic Characterisation of La1+xSr1–xCo0.5M0.5O4±δ (M = Cr, Mn)

“…Oxide ion vacancies in these materials are disordered and confined to the equatorial (Co/M)O 2 planes of the K 2 NiF 4 structure (O1 in Figure 1). An attempt to fit a model in which oxide ion vacancies are distributed between axial and equatorial oxygen sites 13 proved unstable. An associated twisting of the (Co/M)O 6 octahedra around the z ‐axis is observed, which transforms the oxide ions at (0.5, 0, 0) to the split position (0.5, y , 0), similar to that observed in La 1+ x Sr 1– x C 0.5 Fe 0.5 O 4– δ 9.…”