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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: Pressure Effects on Tc and Structure in Overdoped TlSr2CaCu2O7-δ
Author(s): Y. Shimakawa,J.D. Jorgensen,B.A. Hunter,H. Shaked, R.L. Hitterman,Y. Kubo,T. Kondo,T. Manako, et al.
Publication: Physica C Volume: 253 Issue: Not Available Year: 1995 Page(s): 71-78
Editor(s): Not Available
Publisher: Elsevier Science Publishers B.V.
Language: English
Notes: et al. = H. Takahashi, N. Mori
Keywords: Material Specification, Crystallography, Critical Temperature, Resistivity (normal state)

Materials and Properties

Tl:1212; [Tl-Sr-Ca-Cu-O]
Material Specification for Tl:1212; [Tl-Sr-Ca-Cu-O] Process:
Notes: The authors cite Y. Kubo et al., Phys. Rev. B, Vol. 45, 5553 (1992), and summarize the procedure as follows. "Samples were confirmed to be single phase by both X-ray and neutron diffraction. An oxygen annealed sample showed metallic conductivity but no superconductivity above 4 K. Samples reduced in an argon atmosphere showed superconductivity in both resistivity and dimagnetism measurements." No additional processing details were noted.
Formula: TlSr2CaCu2O7-x
Informal Name: Tl:1212
Chemical Family: Tl-Sr-Ca-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-Sr-Ca-Cu-O]
Crystal System: Tetragonal
Formula Units per Cell:
Space Group: P4/mmm
Cell Parameters
Pressure (GPa) Temp K a Å b Å c Å
0.000 296 3.79333(4) -- 12.1259(2)
0.155 296 3.79164(6) -- 12.1115(3)
0.310 296 3.78856(4) -- 12.1044(2)
0.463 296 3.78856(4) -- 12.1044(2)
0.600 296 3.78746(4) -- 12.0993(3)
Atomic Coordinates
Pressure (GPa) Atom Temp K a-axis b-axis c-axis
0 Tl 296 0 0.080(1) 0.5
0 Sr 296 0.5 0.5 0.2844(1)
0 Ca/Tl 296 0.5 0.5 0
0 Cu 296 0 0 0.1374(1)
0 O(1) 296 0 0.5 0.1295(1)
0 O(2) 296 0 0 0.3343(2)
0 O(3) 296 0.5 0.5 0.5
0.155 Tl 296 0 0.081(1) 0.5
0.155 Sr 296 0.5 0.5 0.2844(1)
0.155 Ca/Tl 296 0.5 0.5 0
0.155 Cu 296 0 0 0.1370(2)
0.155 O(1) 296 0 0.5 0.1295(1)
0.155 O(2) 296 0 0 0.3342(2)
0.155 O(3) 296 0.5 0.5 0.5
0.310 Tl 296 0 0.081(1) 0.5
0.310 Sr 296 0.5 0.5 0.2846(2)
0.310 Ca/Tl 296 0.5 0.5 0
0.310 Cu 296 0 0 0.1373(2)
0.310 O(1) 296 0 0.5 0.1294(1)
0.310 O(2) 296 0 0 0.3341(2)
0.310 O(3) 296 0.5 0.5 0.5
0.463 Tl 296 0 0.080(1) 0.5
0.463 Sr 296 0.5 0.5 0.2844(1)
0.463 Ca/Tl 296 0.5 0.5 0
0.463 Cu 296 0 0 0.1371(2)
0.463 O(1) 296 0 0.5 0.1295(1)
0.463 O(2) 296 0 0 0.3341(2)
0.463 O(3) 296 0.5 0.5 0.5
0.600 Tl 296 0 0.080(2) 0.5
0.600 Sr 296 0.5 0.5 0.2842(2)
0.600 Ca/Tl 296 0.5 0.5 0
0.600 Cu 296 0 0 0.1372(2)
0.600 O(1) 296 0 0.5 0.1295(1)
0.600 O(2) 296 0 0 0.3342(2)
0.600 O(3) 296 0.5 0.5 0.5
Measurement Method: Neutron diffraction
The authors cite J.D. Jorgensen et al., Physica C, Vol. 171, 93 (1990), and summarize the procedure as follows. "The crystal structures at room temperature under pressure up to 0.6 GPa were investigated by neutron powder diffraction. Time-of-flight neutron diffraction data were taken at the Special Environment Powder Diffractometer (SEPD) at Argonne's Intense Pulsed Neutron Source (IPNS). A helium gas pressure cell was used to achieve hydrostatic conditions and precise pressure control and measurement. The crystal structures were refined by the Rietveld technique..."

Cautions: Evaluated Data
"Structural parameters versus pressure (are given) for the superconducting Tl-1212 sample with Tc of about 60 K. The occupancies for the Ca and O(3) sites are fixed at Ca/Tl = 0.80/0.20 and 0.862, respectively. The chemical formula is TlSr2Ca0.8Tl0.2)Cu2O6.862."
Critical Temperature for Tl:1212; [Tl-Sr-Ca-Cu-O]
dTc/dP (K/GPa) Critical Temperature (K)
-0.2 35.2
-0.6 51.8
-1.1 72.0
Measurement Method: Four-probe resistance
The authors cite N. Mori et al., J. Phys. Soc. Jpn., Vol. 59, 3839 (1990), and summarize the procedure as follows. "Resistivities were measured by the conventional four-point probe method. The sample was set in a Teflon cell filled with a fluid Fluorinert pressure medium. A piston-cylinder device was used to generate nearly hydrostatic pressure up to 1.5 GPa." No additional measurement details were noted.

Cautions: Evaluated Data
Resistivity (normal state) for Tl:1212; [Tl-Sr-Ca-Cu-O]
Pressure (GPa) Temperature (K) Resistivity (normal state) (mΩ·cm)
0.5 60.2 0.00
0.5 62.9 0.00
0.5 65.6 0.01
0.5 67.1 0.02
0.5 67.6 0.03
0.5 67.9 0.05
0.5 68.4 0.11
0.5 68.7 0.21
0.5 69.0 0.30
0.5 69.3 0.35
0.5 69.4 0.40
0.5 69.7 0.44
0.5 70.2 0.47
0.5 70.5 0.49
0.5 71.4 0.53
0.5 72.7 0.56
0.5 74.0 0.58
0.5 76.5 0.59
0.5 78.2 0.60
0.5 79.8 0.61
1.0 60.3 0.00
1.0 62.3 0.00
1.0 64.5 0.01
1.0 66.0 0.01
1.0 66.5 0.02
1.0 67.0 0.08
1.0 67.6 0.20
1.0 68.0 0.30
1.0 68.3 0.35
1.0 68.6 0.40
1.0 68.9 0.43
1.0 69.6 0.48
1.0 70.3 0.50
1.0 72.0 0.55
1.0 73.7 0.57
1.0 76.2 0.58
1.0 77.9 0.59
1.0 79.8 0.60
1.5 60.2 0.00
1.5 62.2 0.01
1.5 64.3 0.01
1.5 65.6 0.02
1.5 66.2 0.06
1.5 66.6 0.18
1.5 67.3 0.29
1.5 67.7 0.38
1.5 68.3 0.43
1.5 68.6 0.47
1.5 69.1 0.48
1.5 69.9 0.51
1.5 71.1 0.54
1.5 72.3 0.56
1.5 73.6 0.57
1.5 75.3 0.58
1.5 76.8 0.60
1.5 78.4 0.60
1.5 79.9 0.61
Measurement Method: Four-probe resistance
The authors cite N. Mori et al., J. Phys. Soc. Jpn., Vol. 59, 3839 (1990), and summarize the procedure as follows. "Resistivities were measured by the conventional four-point probe method. The sample was set in a Teflon cell filled with a fluid Fluorinert pressure medium. A piston-cylinder device was used to generate nearly hydrostatic pressure up to 1.5 GPa." No additional measurement details were noted.

Cautions: Evaluated Data
"Temperature dependences of resistivity... (are given) for the Tl-1212 sample with an ambient pressure Tc of 72.0 K." Digitized data were obtained from Figure 2 of the paper.