Material Specification for Tl:1212; [Tl(Hg)-Sr-Ca(Y)-Cu-O]
Process: Solid State Reaction
Notes: "High-purity powders of Tl2O3, HgO, SrO2, CaO, Y2O3, Y2O3, and CuO were weighed in the appropriate proportions... The powders were then mixed using a mortar and pestle and pressed into a pellet (10 mm in diameter and 3 mm in thickness) under a pressure of 5 ton/cm2. The pellets were wrapped in gold foil to prevent both loss of thallium and mercury and reaction with quartz at elevated temperatures, then encapsulated in an evacuated (oxygen pressure (0.01 Pa =... 10-4 Torr) quartz tube. Subsequently, the samples were heated inside a furnace at a heating rate of 10 °C/min up to 950 °C for 3 h and then cooled down to room temperature at a cooling rate of 5°C/min... Bar-shaped samples (1.5 mm x 2 mm x 10 mm) were cut from the sintered pellets..."
Formula: Tl0.5Hg0.5Sr2Ca1-xYxCu2O7-y
Informal Name: Tl:1212
Chemical Family: Tl(Hg)-Sr-Ca(Y)-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Crystallography for Tl:1212; [Tl(Hg)-Sr-Ca(Y)-Cu-O]
| Crystal System: | Tetragonal |
| Formula Units per Cell: | |
| Space Group: |
P4/mmm
|
Cell Parameters
| x of Yx (formula units) |
Temp
K
|
a
Å
|
b
Å
|
c
Å
|
| 0.5 |
296 |
3.8050(3) |
-- |
12.011(1) |
Measurement Method: X-ray diffraction
"X-ray diffraction... analyses were performed using a Philips PW1710 X-ray diffractometer with a CuKα radiation." No additional measurement details were noted.
Cautions: Evaluated Data
Critical Temperature for Tl:1212; [Tl(Hg)-Sr-Ca(Y)-Cu-O]
| x of Yx (formula units) |
Tc onset (K) |
Tc magnetic (K) |
Critical Temperature (K) |
| 0.3 |
100 |
92 |
76 |
| 0.5 |
82 |
-- |
34 |
Measurement Method: Four-probe method
"A standard four-probe method was used for the electrical resistance measurements. The electrical contacts to the sample were made by fine copper wires with a conductive silver paint; the applied current was 1 mA. The temperature was recorded using a calibrated silicon diode sensor located close to the sample."
Cautions: Evaluated Data
Magnetic Susceptibility for Tl:1212; [Tl(Hg)-Sr-Ca(Y)-Cu-O]
| x of Yx (formula units) |
Temperature (K) |
Magnetic Susceptibility (arbitrary) |
| 0.3 |
5 |
-0.014 |
| 0.3 |
20 |
-0.013 |
| 0.3 |
35 |
-0.012 |
| 0.3 |
50 |
-0.010 |
| 0.3 |
66 |
-0.008 |
| 0.3 |
80 |
-0.003 |
| 0.3 |
86 |
-0.0009 |
| 0.3 |
88 |
-0.0004 |
| 0.3 |
89 |
-0.0002 |
| 0.3 |
90 |
-0.0001 |
| 0.3 |
92 |
0 |
| 0.3 |
95 |
0 |
Measurement Method: SQUID magnetometer
"Low field magnetization data (796 A/m = 10 Oe, field cooled) were taken from a superconducting quantum interference device (SQUID) magnetometer (Quantum Design)." No additional measurement details were noted.
Cautions: Evaluated Data
Digitized data were obtained from Figure 5 of the paper.
