Material Specification for Tl:221; [Tl-Ba-Cu-O]
Process: Solid State Reaction
Notes: "Stoichiometric proportions of Tl2O3, BaO2, and CuO corresponding to the formula Tl2Ba2Cu1O6 were ground, pressed together, and heated in a 100 mm long by 8 mm diameter gold tube, pinched at the ends but not hermetically sealed... These samples were heated at 700 °C/h and held near 815 °C for 6 hours, then reheated at 50 °C/h (to 815 °C for 8 h. The samples were annealed according to the schedule):
7 h, 840 °C, gold tube;
17 h, 840 °C, gold tube;
21 h, 840 °C, gold tube
quenched."
Formula: Tl2Ba2CuO6
Informal Name: Tl:221
Chemical Family: Tl-Ba-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Crystallography for Tl:221; [Tl-Ba-Cu-O]
| Crystal System: | Orthorhombic |
| Formula Units per Cell: | |
| Space Group: |
A2aa
|
Cell Parameters
| Occupancy () |
Temp
K
|
a
Å
|
b
Å
|
c
Å
|
| -- |
5 |
5.4598(3) |
5.4645(3) |
23.1869(8) |
| -- |
300 |
5.4684(4) |
5.4727(4) |
23.2382(9) |
Atomic Coordinates
| Occupancy () |
Atom |
Temp
K
|
a-axis |
b-axis |
c-axis |
| 7.00(10) |
Tl |
5 |
0 |
0.2466(10) |
0.4531(1) |
| 7.59(11) |
Ba |
5 |
0 |
0.7510(18) |
0.3344(2) |
| 4 |
Cu |
5 |
0 |
0.25 |
0.25 |
| 7.52(10) |
O(1) |
5 |
0.25 |
0 |
0.2508(5) |
| 7.07(11) |
O(2) |
5 |
0 |
0.2452(17) |
0.3666(1) |
| 7.25(12) |
O(3) |
5 |
0.4685(28) |
0.3124(15) |
0.4604(2) |
| 7.35(11) |
Tl |
300 |
0 |
0.2456(11) |
0.4532(1) |
| 8.23(12) |
Ba |
300 |
0 |
0.7515(19) |
0.3335(2) |
| 4 |
Cu |
300 |
0 |
0.25 |
0.25 |
| 8.07(12) |
O(1) |
300 |
0.25 |
0 |
0.2507(7) |
| 7.52(12) |
O(2) |
300 |
0 |
0.2433(17) |
0.3675(1) |
| 7.14(13) |
O(3) |
300 |
0.4755(38) |
0.3111(16) |
0.4605(3) |
Measurement Method: Neutron diffraction
The authors cite A.W. Hewat et al., Physica C, Vol. 152, 438 (1988), and summarize the procedure as follows. "Neutron diffraction was performed on typically (about) 5 g samples at 5 K and a 300 K on D2B at ILL Grenoble..."
Cautions: Evaluated Data
Critical Temperature for Tl:221; [Tl-Ba-Cu-O]
| Critical Temperature (K) |
| 70 |
Measurement Method: Ac susceptibility
The authors cite J.J. Capponi et al., Europhys. Lett., Vol. 3, 1301 (1987), and summarize the procedure as follows. "T
c was determined by measurement of the a.c. susceptibility..."
Cautions: Evaluated Data
Magnetic Susceptibility for Tl:221; [Tl-Ba-Cu-O]
| Temperature (K) |
Magnetic Susceptibility (arbitrary) |
| 12 |
-0.99 |
| 37 |
-0.97 |
| 54 |
-0.85 |
| 60 |
-0.40 |
| 65 |
-0.15 |
| 77 |
0.00 |
| 90 |
0.00 |
Measurement Method: Ac susceptibility
The authors cite J.J. Capponi et al., Europhys. Lett., Vol. 3, 1301 (1987), and summarize the procedure as follows. "T
c was determined by measurement of the a.c. susceptibility..."
Cautions: Evaluated Data
Digitized data were obtained from Figure 2 of the paper.
