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: TlBa2-xLa2+xCu2O9±δ: A New 42 K Superconductor, Intergrowth of "1201" and "0201" Structures
Author(s): C. Martin, A. Maignan, M. Huve, M. Hervieu, C. Michel, and B. Raveau
Publication: Physica C Volume: 179 Issue: Not Available Year: 1991 Page(s): 1-8
Editor(s): Not Available
Publisher: Elsevier Science Publishers B.V.
Language: English
Notes: Not Available
Keywords: Material Specification, Crystallography, Critical Temperature

Materials and Properties

TlLa:1222; [Tl-Ba(La)-Cu-O]
Material Specification for TlLa:1222; [Tl-Ba(La)-Cu-O] Process: Solid State Reaction
Notes: "The samples were prepared from mixtures of Tl2O3, BaO2, La2O3 and CuO in the appropriate ratios. The powders were pressed into pellets and sealed in evacuated silica ampoules; different thermal treatments were tested, the best results were obtained when heating at 890 °C during three days and cooling to room temperature in 50 h."
Formula: TlBa1.6La2.4Cu2O9-x
Informal Name: TlLa:1222
Chemical Family: Tl-Ba(La)-Cu-O
Chemical Class: Oxide
Structure Type:
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Crystallography for TlLa:1222; [Tl-Ba(La)-Cu-O]
Crystal System: Tetragonal
Formula Units per Cell:
Space Group: I4/mmm
Cell Parameters
Temp K a Å b Å c Å
296 3.8110(2) -- 31.556(2)
Atomic Coordinates
Atom Temp K a-axis b-axis c-axis
Tl 296 0.0 0.0 0.0
Ba 296 0.5 0.5 0.0850(1)
La 296 0.5 0.5 0.2044(2)
Cu 296 0.0 0.0 0.1466(4)
O(1) 296 0.5 0.5 0.0
O(2) 296 0.0 0.0 0.063(1)
O(3) 296 0.5 0.0 0.1458(9)
O(4) 296 0.0 0.0 0.218(1)
Measurement Method: X-ray diffraction
"The powder X-ray diffraction pattern was registered by step scanning over an angular range of 15° ≤ 2_ ≤ 100° with an increment of 0.02° (2θ) by means of a Philips diffractometer using the CuKα radiation."

Cautions: Evaluated Data
Critical Temperature for TlLa:1222; [Tl-Ba(La)-Cu-O]
Annealing Time (h) Critical Temperature (K)
0.0 35
0.5 42
Measurement Method: Ac susceptibility
Measurements were made in a field of 0.5 mT (5 G). "Ar/H2 annealings were performed at 270 °C..."

Cautions: Unevaluated Data