Material Specification for Hg:121; [Hg-Ba-Cu-O]
Process: Solid State Reaction
Notes: The authors cite De Leeuw et al., Physica C, Vol. 152, 39-49 (1988), and summarize the procedure as follows. "The samples were prepared by solid state reaction between stoichiometric mixtures of Ba2CuO3+δ and yellow HgO (98% purity, Aldrich). The precursor Ba2CuO3+δ was obtained by the same type of reaction between BaO2 (95% purity, Aldrich) and CuO (NormaPur, Prolabo) at 930 °C in oxygen... The powders were ground in an agate mortar and placed in silica tubes. All these operations, were carried out in a dry box. After evacuation, the tubes were sealed, placed in a steel containers... and heated for 5 h to reach (about) 800 °C. The samples were then cooled in the furnace, reaching room temperature after (about) 10 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
| Occupancy () |
Temp
K
|
a
Å
|
b
Å
|
c
Å
|
| -- |
296 |
3.87766(4) |
-- |
9.5073(1) |
Atomic Coordinates
| Occupancy () |
Atom |
Temp
K
|
a-axis |
b-axis |
c-axis |
| 1.00 |
Hg |
296 |
0 |
0 |
0 |
| 1.00 |
Ba |
296 |
0.5 |
0.5 |
0.2979(1) |
| 1.00 |
Cu |
296 |
0 |
0 |
0.5 |
| 1.00 |
O(1) |
296 |
0.5 |
0 |
0.5 |
| 1.00 |
O(2) |
296 |
0 |
0 |
0.206(2) |
| 0.10(3) |
O(3) |
296 |
0.5 |
0.5 |
0 |
Measurement Method: X-ray diffraction
"... X-ray powder data were collected by a θ/2θ STADI P diffractometer in transmission mode... using monochromatized CuKα
1 radiation (wavelength =1.54056 σ)... The experimental conditions were as follows: 2θ range = 6-115° (0.02° steps) with fixed counting time 60s and a rotating sample. An absportion correction was applied and the sample thickness was calculated from the primary beam absorption... The structural refinements were done by the Rietveld method."
Cautions: Evaluated Data
Critical Temperature for Hg:121; [Hg-Ba-Cu-O]
| Critical Temperature (K) |
| 94 |
Measurement Method: Ac susceptibility
Cautions: Unevaluated Data
No measurement details were noted.
