Material Specification for Hg:121; [Hg-Ba-Cu-O]
Process: Solid State Reaction
Notes: "Samples... were prepared from stoichiometric mixtures of HgO and Ba2CuO3 which were intimately ground and pressed into pellets. The Ba2CuO3 precursor was prepared from BaO and CuO fired at 930 °C in a flowing 20% O2/Ar gas mixture for 24 h with intermediate grindings. Pellets of the material were then placed in quartz tubes, evacuated... and sealed. These were then placed in a preheated furnace at 845 °C and fired for 8 h."
Formula: HgBa2CuO4+x
Informal Name: Hg:121
Chemical Family: Hg-Ba-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Crystallography for Hg:121; [Hg-Ba-Cu-O]
| Crystal System: | Tetragonal |
| Formula Units per Cell: | |
| Space Group: |
P4/mmm
|
Cell Parameters
| Sample Condition () |
Occupancy () |
Temp
K
|
a
Å
|
b
Å
|
c
Å
|
| Oxidized |
-- |
10 |
3.86620(3) |
-- |
9.4899(1) |
| Oxidized |
-- |
50 |
3.86640(3) |
-- |
9.4904(2) |
| Oxidized |
-- |
100 |
3.86740(3) |
-- |
9.4938(2) |
| Oxidized |
-- |
150 |
3.86888(4) |
-- |
9.4987(2) |
| Oxidized |
-- |
200 |
3.87083(4) |
-- |
9.5045(2) |
| Oxidized |
-- |
250 |
3.87304(4) |
-- |
9.5104(2) |
| Oxidized |
-- |
296 |
3.87503(2) |
-- |
9.5132(1) |
| Oxidized |
-- |
300 |
3.87533(4) |
-- |
9.5162(2) |
| Reduced |
-- |
296 |
2.88881(3) |
-- |
9.5398(1) |
Atomic Coordinates
| Sample Condition () |
Occupancy () |
Atom |
Temp
K
|
a-axis |
b-axis |
c-axis |
| Oxidized |
0.93(1) |
Hg |
296 |
0 |
0 |
0 |
| Oxidized |
2 |
Ba |
296 |
0.5 |
0.5 |
0.2981(1) |
| Oxidized |
1 |
Cu |
296 |
0 |
0 |
0.5 |
| Oxidized |
2 |
O(1) |
296 |
0.5 |
0.5 |
0 |
| Oxidized |
2 |
O(2) |
296 |
0 |
0 |
0.2078(1) |
| Oxidized |
0.059(6) |
O(3) |
296 |
0.5 |
0.5 |
0 |
| Oxidized |
0.09(1) |
O(4) |
296 |
0.5 |
0 |
0.043(4) |
| Reduced |
0.91(2) |
Hg |
296 |
0 |
0 |
0 |
| Reduced |
2 |
Ba |
296 |
0.5 |
0.5 |
0.3016(2) |
| Reduced |
1 |
Cu |
296 |
0 |
0 |
0.5 |
| Reduced |
2 |
O(1) |
296 |
0.5 |
0.5 |
0 |
| Reduced |
2 |
O(2) |
296 |
0 |
0 |
0.2061(2) |
| Reduced |
0.008(7) |
O(3) |
296 |
0.5 |
0.5 |
0 |
| Reduced |
0.10(2) |
O(4) |
296 |
0.5 |
0 |
0.036(5) |
Measurement Method: Neutron diffraction
"Neutron powder diffraction data were collected... using the special environment powder diffractometer (SEPD) at Argonne's intense pulsed neutron source (IPNS)... the room temperature data were collected with the sintered pellets supported in the neutron beam with no sample container, with the thin dimension of the pellets along the direction of the incident beam. Low temperature data were collected with the sample in the form of loose powder contained in an indium-sealed thin-walled vanadium can (6.35 mm = 0.25 inches) in a diameter filled with helium exchange gas... The powder diffraction data were analyzed with the Rietveld technique, using the IPNS time-of-flight Rietveld code. Only data from the high-resolution back scattering detector banks (2θ=145°) were used in the refinements."
Cautions: Evaluated Data
Critical Temperature for Hg:121; [Hg-Ba-Cu-O]
| Sample Condition () |
Critical Temperature (K) |
| Oxidized |
95 |
| Reduced |
59 |
Measurement Method: Ac susceptibility
"Susceptibility was measured with a Lake Shore Cryotronics AC susceptometer in a (0.1 mT = 1 G) field at 100 Hz." No additional measurement details were noted.
Cautions: Evaluated Data
Magnetic Susceptibility for Hg:121; [Hg-Ba-Cu-O]
| Sample Condition () |
Temperature (K) |
Magnetic Susceptibility (arbitrary) |
| Reduced |
10 |
-0.48 |
| Reduced |
30 |
-0.47 |
| Reduced |
40 |
-0.45 |
| Reduced |
50 |
-0.42 |
| Reduced |
53 |
-0.40 |
| Reduced |
55 |
-0.30 |
| Reduced |
58 |
-0.02 |
| Reduced |
60 |
0.00 |
| Reduced |
100 |
0.00 |
| Oxidized |
10 |
-1.00 |
| Oxidized |
30 |
-0.98 |
| Oxidized |
40 |
-0.94 |
| Oxidized |
50 |
-0.90 |
| Oxidized |
60 |
-0.85 |
| Oxidized |
70 |
-0.75 |
| Oxidized |
80 |
-0.62 |
| Oxidized |
90 |
-0.46 |
| Oxidized |
92 |
-0.40 |
| Oxidized |
95 |
-0.06 |
| Oxidized |
96 |
0.00 |
| Oxidized |
100 |
0.00 |
Measurement Method: Ac susceptibility
"Susceptibility was measured with a Lake Shore Cryotronics AC susceptometer in a (0.1 mT = 1 G) field at 100 Hz." No additional measurement details were noted.
Cautions: Evaluated Data
Digitized data were obtained from Figure 2 of the paper.
