OXYGEN STOICHIOMETRY IN BA2YCU3OX

被引：418

作者：

GALLAGHER, PK

OBRYAN, HM

SUNSHINE, SA

MURPHY, DW

机构：

[1] AT&T Bell Lab, Murray Hill, NJ,, USA, AT&T Bell Lab, Murray Hill, NJ, USA

来源：

MATERIALS RESEARCH BULLETIN | 1987年 / 22卷 / 07期

关键词：

BARIUM COMPOUNDS - Physical Chemistry - CERAMIC MATERIALS - Low Temperature Properties - SPECTROSCOPIC ANALYSIS - X-RAY ANALYSIS - YTTRIUM COMPOUNDS - Physical Chemistry;

D O I：

10.1016/0025-5408(87)90099-7

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Thermogravimetry (TG), evolved gas analysis (EGA), x-ray powder diffraction and dilatometry have been used to characterize the oxygen stoichiometry in the 93K superconductor Ba//2YCu//3O//x (7. 0 greater than x greater than 6. 0). Above 400 degree C equilibration with ambients containing oxygen occurs rapidly. A reversible structural transformation occurs with changing oxygen stoichiometry going from orthorhombic at x equals 7. 0 to tetragonal at x equals 6. 0. The upper limit of x, which is achieved by annealing in oxygen at 400-500 degree C, shows the sharpest superconducting T//c's. The tetragonal phase is not superconducting. Structural models are proposed for the tetragonal structure.

引用

页码：995 / 1006

页数：12

共 25 条

[1] POSSIBLE HIGH-TC SUPERCONDUCTIVITY IN THE BA-LA-CU-O SYSTEM [J].