TY - JOUR

T1 - Crystal structure and charge localization in Pb2Sr2Y1-xCaxCu3O8 for x=0.0-0.5

AU - Jørgensen, J.-E.

AU - Andersen, N.H.

PY - 1993/12/1

Y1 - 1993/12/1

N2 - Neutron powder diffraction studies of Pb2Sr2Y1-xCaxCu3O8 samples for x = 0.0-0. 5 have shown that Ca doping causes a positive charge transfer to the CuO2 as well as to the PbO layers. The bond-valency sum for the Cu ions in the CuO2 layer increases as a function of x, while the bond-valency sum for the Pb ions increases up to x = 0.4 and is then saturated. The axial Cu-0 bond length shows a maximum at x = 0.4, and the shortest axial Cu-0 bond length was found for x = 0.5. The x = 0.5 sample was found to become superconducting with an onset temperature of 79 K. The distance between the Cu ions in the CuO2-(Y, Ca)-CuO2 sandwich is increased by 0.14 angstrom by going from x = 0.0 to 0.5.

AB - Neutron powder diffraction studies of Pb2Sr2Y1-xCaxCu3O8 samples for x = 0.0-0. 5 have shown that Ca doping causes a positive charge transfer to the CuO2 as well as to the PbO layers. The bond-valency sum for the Cu ions in the CuO2 layer increases as a function of x, while the bond-valency sum for the Pb ions increases up to x = 0.4 and is then saturated. The axial Cu-0 bond length shows a maximum at x = 0.4, and the shortest axial Cu-0 bond length was found for x = 0.5. The x = 0.5 sample was found to become superconducting with an onset temperature of 79 K. The distance between the Cu ions in the CuO2-(Y, Ca)-CuO2 sandwich is increased by 0.14 angstrom by going from x = 0.0 to 0.5.

KW - Materialer med særlige fysiske og kemiske egenskaber

U2 - 10.1016/0921-4534(93)90263-P

DO - 10.1016/0921-4534(93)90263-P

M3 - Journal article

VL - 218

SP - 43

EP - 50

JO - Physica C: Superconductivity and its Applications

JF - Physica C: Superconductivity and its Applications

SN - 0921-4534

IS - 1-2

ER -