Material Specification for PbSr:2213; [Pb-Sr-Y(Ca)-Cu-O]
Process: Solid State Reaction
Notes: The authors cite R.J. Cava et al., Nature, Vol. 336, 211 (1988), and summarize the procedure as follows. "Crystals... are synthesized using a modification of the two-step flux growth method... A precursor, Sr2Y0.5Ca0.5Cu3O6+y (or SYCCO), which is made by reacting stoichiometric amounts of SrCO3, Y2O3, CaCO3, and CuO at 950 °C for twelve hours in air, is combined with a PbO and NaCl co-flux in two different starting compositions. The molar ratios of SYCCO:PbO:NaCl for these two starting compositions are 2:9:60 and 1:7:17. The covered platinum crucible is heated using a tube furnace in nitrogen to 1050 °C, cooled at a rate of 5-10 °C/h to 700 °C, and then allowed to reach room temperature over a period of eight hours. A NaCl layer, which is easily removed mechanically, lines the top of the crucible. The melt below contains the crystals... embedded in a PbO-rich flux mixture. The black crystals can be extracted undamaged from the PbO flux with methanol solvent in an ultrasonic bath. ... Typical dimensions of the crystals grown by this technique are 1x1x0.25 mm3."
Formula: Pb2Sr2Y1-xCaxCu3O8+y
Informal Name: PbSr:2213
Chemical Family: Pb-Sr-Y(Ca)-Cu-O
Chemical Class: Oxide
Structure Type: Single Crystal
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Crystallography for PbSr:2213; [Pb-Sr-Y(Ca)-Cu-O]
| Crystal System: | Orthorhombic |
| Formula Units per Cell: | |
| Space Group: |
|
Cell Parameters
|
Temp
K
|
a
Å
|
b
Å
|
c
Å
|
| 296 |
5.383(1) |
5.423(1) |
15.765(2) |
Measurement Method: Guinier x-ray camera
"The crystals... have been investigatd by the Guinier powder camera method... The results from the Guinier data (were) obtained on powder ground from a single crystal..."
Cautions: Evaluated Data
Critical Temperature for PbSr:2213; [Pb-Sr-Y(Ca)-Cu-O]
| Tc onset (K) |
Critical Temperature (K) |
| 85.5 |
84 |
Measurement Method: Four-probe method
"The DC resistivity measurements were performed using a standard four-terminal arrangement. The magnitude of the resistivity was calculated using the van der Pauw method. Four contacts were placed on the perimeter of the sample in the plane perpendicular to the c-axis. The contacting procedure was accomplished by attaching 25 µm gold wires to the sample with silver paint and then... annealed for a total of 15 h at 600 °C in nitrogen."
Cautions: Evaluated Data
The value of T
c was obtained from the resistivity data of Fig. 3b.
Resistivity (normal state) for PbSr:2213; [Pb-Sr-Y(Ca)-Cu-O]
| Direction () |
Temperature (K) |
Resistivity (normal state) (mΩ·cm) |
| ab-plane |
82.0 |
0.00 |
| ab-plane |
83.1 |
0.001 |
| ab-plane |
84.0 |
0.003 |
| ab-plane |
84.2 |
0.013 |
| ab-plane |
84.9 |
0.075 |
| ab-plane |
85.1 |
0.136 |
| ab-plane |
85.5 |
0.214 |
| ab-plane |
87.5 |
0.229 |
| ab-plane |
89.3 |
0.241 |
| ab-plane |
120 |
0.38 |
| ab-plane |
160 |
0.50 |
| ab-plane |
200 |
0.61 |
| ab-plane |
245 |
0.72 |
| c-axis |
84.2 |
25.3 |
| c-axis |
84.6 |
29.7 |
| c-axis |
87.1 |
33.7 |
| c-axis |
95.8 |
34.8 |
| c-axis |
115.2 |
34.4 |
| c-axis |
139.0 |
34.7 |
| c-axis |
147.6 |
35.4 |
| c-axis |
202.0 |
39.7 |
| c-axis |
247.8 |
45.4 |
Measurement Method: Four-probe method
"The DC resistivity measurements were performed using a standard four-terminal arrangement. The magnitude of the resistivity was calculated using the van der Pauw method. Four contacts were placed on the perimeter of the sample in the plane perpendicular to the c-axis. The contacting procedure was accomplished by attaching 25 µm gold wires to the sample with silver paint and then... annealed for a total of 15 h at 600 °C in nitrogen."
Cautions: Evaluated Data
Digitized data were obtained from Figure 3a, 3b, and 4 of the paper.
