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NIST High Temp. Superconducting Materials (HTS) Database:

NIST Standard Reference Database 62

Last Update to Data Content: 1996

DOI: https://doi.org/10.18434/T4KP8J

Bibliographic Information

Title: Crystal Structure of HgBa2Ca2Cu3O8+δ at High Pressure (to 8.5 GPa) Determined by Powder Neutron Diffraction
Author(s): A.R. Armstrong, W.I.F. David, I. Gameson, P.P. Edwards, J.J. Capponi, P. Bordet, and M. Marezio
Publication: Physical Review B Volume: 52 Issue: 1 Year: 1995 Page(s): 15551-15557
Editor(s): Not Available
Publisher: American Physical Society
Language: English
Notes: Not Available
Keywords: Material Specification, Crystallography, Critical Temperature, Magnetic Susceptibility, Bulk Modulus

Materials and Properties

Hg:1223; [Hg-Ba-Ca-Cu-O]
Material Specification for Hg:1223; [Hg-Ba-Ca-Cu-O] Process: Solid State Reaction
Notes: The authors cite O. Chmaissem et al., Physica C, Vol. 217, 265 (1993), and summarize the procedure as follows. "A mixed precursor with the nominal composition Ba2Ca2Cu3Ox was prepared from a stoichiometric mixture of the component nitrates under flowing oxygen at 925 °C for 72 h with three intermediate grindings. A stoichiometric amount of yellow HgO was added to this precursor and the mixture placed in a gold capsule adapted for high pressure sythesis. The sample was pressurized to 1.8 GPa over the course of 20 min and then heated to 880 °C in 40 min. The temperature and pressure were then maintained for 1.6 h to 1.8 h before switching the furnace off and decreasing the pressure to ambient over a period of 20 min."
Formula: HgBa2Ca2Cu3O8+x
Informal Name: Hg:1223
Chemical Family: Hg-Ba-Ca-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:

Crystallography for Hg:1223; [Hg-Ba-Ca-Cu-O]
Crystal System: Tetragonal
Formula Units per Cell:
Space Group:
Cell Parameters
Pressure (GPa) Temp K a Å b Å c Å
0.0 296 3.85159(3) -- 15.7644(4)
0.5 296 3.8481(2) -- 15.740(3)
3.5 296 3.8089(3) -- 15.400(4)
6.0 296 3.7822(5) -- 15.180(6)
8.5 296 3.7608(6) -- 15.018(7)
Atomic Coordinates
Pressure (GPa) Atom Temp K a-axis b-axis c-axis
0 Hg 296 0 0 0
0 Ba 296 0.5 0.5 0.1696(4)
0 Ca 296 0.5 0.5 0.3950(5)
0 Cu(1) 296 0 0 0.5
0 Cu(2) 296 0 0 0.2986(3)
0 O(1) 296 0.5 0 0.5
0 O(2) 296 0.5 0 0.3014(3)
0 O(3) 296 0 0 0.1256(4)
0 O(4) 296 0.5 0.5 0
0.5 Hg 296 0 0 0
0.5 Ba 296 0.5 0.5 0.1678(9)
0.5 Ca 296 0.5 0.5 0.3950(12)
0.5 Cu(1) 296 0 0 0.5
0.5 Cu(2) 296 0 0 0.2973(6)
0.5 O(1) 296 0.5 0 0.5
0.5 O(2) 296 0.5 0 0.3029(7)
0.5 O(3) 296 0 0 0.1256(7)
0.5 O(4) 296 0.5 0.5 0
3.5 Hg 296 0 0 0
3.5 Ba 296 0.5 0.5 0.1674(12)
3.5 Ca 296 0.5 0.5 0.3999(15)
3.5 Cu(1) 296 0 0 0.5
3.5 Cu(2) 296 0 0 0.2963(17)
3.5 O(1) 296 0.5 0 0.5
3.5 O(2) 296 0.5 0 0.3015(9)
3.5 O(3) 296 0 0 0.1256(10)
3.5 O(4) 296 0.5 0.5 0
6.0 Hg 296 0 0 0
6.0 Ba 296 0.5 0.5 0.1661(12)
6.0 Ca 296 0.5 0.5 0.3965(17)
6.0 Cu(1) 296 0 0 0.5
6.0 Cu(2) 296 0 0 0.2964(10)
6.0 O(1) 296 0.5 0 0.5
6.0 O(2) 296 0.5 0 0.2997(10)
6.0 O(3) 296 0 0 0.1271(12)
6.0 O(4) 296 0.5 0.5 0
8.5 Hg 296 0 0 0
8.5 Ba 296 0.5 0.5 0.1651(13)
8.5 Ca 296 0.5 0.5 0.3931(16)
8.5 Cu(1) 296 0 0 0.5
8.5 Cu(2) 296 0 0 0.2934(9)
8.5 O(1) 296 0.5 0 0.5
8.5 O(2) 296 0.5 0 0.3003(10)
8.5 O(3) 296 0 0 0.1309(13)
8.5 O(4) 296 0.5 0.5 0
Measurement Method: Neutron diffraction
"Time-of-flight powder neutron-diffraction measurements were performed on the high intensity, medium resolutio POLARIS diffractometer at the ISIS facility at the Rutherford Appleton Laboratory. An ambient pressure measurement was made in a cylindrical vanadium can to obtain accurate starting parameters for the refinement of the high-pressure data. ... High-pressure measurements were made using the Paris Edinburgh opposed anvil pressure cell with a sample volume of about 100 mm3. ... High-pressure diffraction data were collected using the detector bands at scattering angles of 82° < 2θ < 96°, which gives data over the d spacing range 0.3 σ < d < 4.3 σ with a resolution of Δd/d of about 0.6%. Each data set was collected over a period of 12-15 h. The data were normalized to remove the wave-length dependence of the incident neutron flux and corrected for the effects of attenuation of the incident and scattered beams by components of the pressure cell. ...applied pressures have been inferred from the applied load given the known behavior of the pressure cell for similar materials. (Hence the rather large errors...) ...two phase refinement was performed using the program FORTY1, also based on the Cambridge Crystallographic Subroutine Library. All positional parameters were refined, along with isotropic thermal parameters for all atoms except O(4) in the Hg planes. Thermal parameters for similar sites in Hg1223 and Hg1234 were constrained to be equal."

Cautions: Evaluated Data
Critical Temperature for Hg:1223; [Hg-Ba-Ca-Cu-O]
Critical Temperature (K)
134 ± 1
Measurement Method: SQUID magnetometer
"Superconducting properties were measured using a dc superconducting quantum interference device magnetometer (Cryogenics Model S100); here the sample vial was lowered into the cryostat and cooled to about 4 K in the absence of any externally generated magnetic field." No additional measurement details were noted.

Cautions: Unevaluated Data
Magnetic Susceptibility for Hg:1223; [Hg-Ba-Ca-Cu-O]
Temperature (K) Magnetic Susceptibility (arbitrary)
8 -0.96
36 -0.94
66 -0.89
85 -0.80
107 -0.62
119 -0.51
128 -0.36
133 -0.12
158 0.00
170 0
213 0
230 0
250 0
Measurement Method: SQUID magnetometer
"Superconducting properties were measured using a dc superconducting quantum interference device magnetometer (Cryogenics Model S100); here the sample vial was lowered into the cryostat and cooled to about 4 K in the absence of any externally generated magnetic field." No additional measurement details were noted.

Cautions: Unevaluated Data
Digitized data were obtained from Figure 2 of the paper.
Bulk Modulus for Hg:1223; [Hg-Ba-Ca-Cu-O]
Temperature (K) Bulk Modulus (GPa)
296 90
Measurement Method: Neutron diffraction
"Time-of-flight powder neutron-diffraction measurements were performed on the high intensity, medium resolutio POLARIS diffractometer at the ISIS facility at the Rutherford Appleton Laboratory. An ambient pressure measurement was made in a cylindrical vanadium can to obtain accurate starting parameters for the refinement of the high-pressure data. ... High-pressure measurements were made using the Paris Edinburgh opposed anvil pressure cell with a sample volume of about 100 mm3. ... High-pressure diffraction data were collected using the detector bands at scattering angles of 82° < 2θ < 96°, which gives data over the d spacing range 0.3 σ < d < 4.3 σ with a resolution of Δd/d of about 0.6%. Each data set was collected over a period of 12-15 h. The data were normalized to remove the wave-length dependence of the incident neutron flux and corrected for the effects of attenuation of the incident and scattered beams by components of the pressure cell. ...applied pressures have been inferred from the applied load given the known behavior of the pressure cell for similar materials. (Hence the rather large errors...) ...two phase refinement was performed using the program FORTY1, also based on the Cambridge Crystallographic Subroutine Library. All positional parameters were refined, along with isotropic thermal parameters for all atoms except O(4) in the Hg planes. Thermal parameters for similar sites in Hg1223 and Hg1234 were constrained to be equal."

Cautions: Evaluated Data