Material Specification for Y:123; [Y-Ba-Cu-O]
Process:
Notes: The authors cite R.J. Cava et al., Nature, Vol. 329, 423 (1987), and summarize the procedure as follows. "Single phase polycrystalline Ba2YCu3O7 pellets were prepared... Oxygen was then removed from the samples by heating 1.0 g pellets in sealed evacuated quartz tubes of 20 cm3 volume for four days at 440 °C with 0-14 pieces of (1.27 cm x 2.54 cm = 0.5 in. x 1.0 in.) area bright Zr foil. For the largest oxygen deficiencies, x = 6.35 and 6.0, the desired oxygen content was not reached after a single annealing step, and so selected samples were re-annealed with new Zr under the same conditions to remove more oxygen. The oxygen content of the samples was derived from the weight change of part of the sample on reduction in N2-15% H2..."
Formula: YBa2Cu3Ox
Informal Name: Y:123
Chemical Family: Y-Ba-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Crystallography for Y:123; [Y-Ba-Cu-O]
| Crystal System: | |
| Formula Units per Cell: | |
| Space Group: |
|
Cell Parameters
| x of Ox (formula units) |
Temp
K
|
a
Å
|
b
Å
|
c
Å
|
| 6.95 |
5 |
3.8136(1) |
3.8845(1) |
11.6603(3) |
| 6.84 |
5 |
3.8153(1) |
3.8848(1) |
11.6692(3) |
| 6.81 |
5 |
3.8163(1) |
3.8845(1) |
11.6739(3) |
| 6.78 |
5 |
3.8170(1) |
3.8836(1) |
11.6768(3) |
| 6.73 |
5 |
3.8193(1) |
3.8835(1) |
11.6832(2) |
| 6.64 |
5 |
3.8224(1) |
3.8811(1) |
11.6912(3) |
| 6.58 |
5 |
3.8252(1) |
3.8786(1) |
11.6987(3) |
| 6.45 |
5 |
3.8293(1) |
3.8750(1) |
11.7101(4) |
| 6.35 |
5 |
3.8580(1) |
3.8580(1) |
11.7913(3) |
| 6.00 |
5 |
3.8544(1) |
3.8544(1) |
11.8175(4) |
Measurement Method: Neutron diffraction
"The samples, sintered disks approximately 10 mm in diameter and 1 mm thick, were sealed in a vanadium can with the disk normal to the incident neutron beam. All measurements were made on D2B at ILL in a helium flow cryostat at 5 K, with eight one-hour scans averaged over different detectors for each sample. The wavelength of 1.5946(3) σ was chosen... The data were analyzed using an early version of the Rietveld profile refinement program."
Cautions: Evaluated Data
Critical Temperature for Y:123; [Y-Ba-Cu-O]
| x of Ox (formula units) |
Critical Temperature (K) |
| 6.95 |
90 |
| 6.84 |
88 |
| 6.81 |
86 |
| 6.73 |
69 |
| 6.64 |
59 |
| 6.58 |
56 |
| 6.45 |
56 |
Measurement Method: SQUID magnetometer
"The superconducting transition temperatures were measured by DC magnetization (SHE SQUID magnetometer) on small pieces of the polycrystalline pellets on cooling in a field of (398 A/m = 5.0 Oe)."
Cautions: Evaluated Data
