OXYGEN CLUSTERING IN 123 COPPER OXIDES HAVING DISORDERED OR EXCESS (GREATER-THAN 7.0) OXYGEN

被引：10

作者：

GOODENOUGH, JB ^{[1
]}

MANTHIRAM, A ^{[1
]}

DAI, Y ^{[1
]}

CAMPION, A ^{[1
]}

机构：

[1] UNIV TEXAS,DEPT CHEM,AUSTIN,TX 78712

来源：

SUPERCONDUCTOR SCIENCE & TECHNOLOGY | 1988年 / 1卷 / 04期

关键词：

Ceramic Materials - Electronic Properties - Oxygen - Yttrium Compounds - Electric Conductivity;

D O I：

10.1088/0953-2048/1/4/007

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

It is shown that in the high-Tc copper oxide superconductors, Tc varies for a given structure with the concentration of mobile holes in excess of the formal Cu(II) oxidation state in CuO2 sheets with a bridging oxygen atom making about 180° Cu-O-Cu interactions. It is also demonstrated by XPS spectroscopy as well as by indirect experiments that, in the YBa2Cu3O6+x (123) structure, the presence of a-axis oxygen in the Cu(1) planes at compositions x > 0.5 leads to the trapping of holes at oxygen-cluster states. We conclude that the π* band holes are in states of primarily O 2pπ character as opposed to Cu 3t2 character and suggest that the critical common feature of the high-Tc copper oxides and Ba2-xKxBiO3 is an overlapping of partially occupied Cu 3e σ* or Bi 6s σ* and O 2ppiπ* bands.

引用

页码：187 / 193

页数：7

共 21 条

[1]

ALARIOFRANCO MA, 1987, NOV FALL M MAT RES S

[2] LOCALIZATION OF CU-3D LEVELS IN THE HIGH-TC SUPERCONDUCTOR YBA2CU3O-7 BY CU-2P X-RAY PHOTOELECTRON-SPECTROSCOPY [J].