Material Specification for La:21; [La(Sr)-Cu-O]
Process: Solid State Reaction
Notes: "The material for the powder diffraction study was prepared from a mixture of SrCO3, CuO, and La2(CO3)3, ball milled, filtered, dried, and fired for 2 h in air at 900 °C, and ball milled, filtered, and redried. The powder was then fired at 1000 °C for one day and 900 °C in flowing O2 for one day and cooled slowly to room temperature in the gas stream."
Formula: La1.85Sr0.15CuO4
Informal Name: La:21
Chemical Family: La(Sr)-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Crystallography for La:21; [La(Sr)-Cu-O]
Crystal System: | |
Formula Units per Cell: | |
Space Group: |
|
Cell Parameters
Temp
K
|
a
Å
|
b
Å
|
c
Å
|
300 |
3.7793(1) |
-- |
13.2260(3) |
60 |
5.3252(1) |
5.3546(1) |
13.1844(1) |
10 |
5.3240(1) |
5.3547(1) |
13.1832(1) |
Atomic Coordinates
Atom |
Temp
K
|
a-axis |
b-axis |
c-axis |
La/Sr |
300 |
0.0 |
0.0 |
0.3605(1) |
Cu |
300 |
0.0 |
0.0 |
0.0 |
O1 |
300 |
0.0 |
0.0 |
0.1824(1) |
O2 |
300 |
0.0 |
0.5 |
0.0 |
Measurement Method: Neutron diffraction
"The neutron diffraction measurements were performed on the high-resolution five-counter powder diffractometer at the National Bureau of Standards, employing neutrons of wavelength 1.5480 σ. The data were collected with a 10' inpile collimator, a 20' monochromatic beam collimator, and a 10' diffracted beam collimator, in the angular range 12-113° (2θ). The portions of the diffraction pattern containing diffraction peaks from the aluminum sample container and the very small amount of chemical impurity were omitted from the refinement. The powder profile refinement was performed using the Rietveld program adapted to the five-detector diffractometer design and modified to allow the refinement of background intensity."
Cautions: Evaluated Data
Temperature[K] | Crystal System | Space Group |
300
|
etragonal |
I4/mmm |
60
|
Orthorhombic |
Bmab |
10 | Orthorhombic | Bmab |
Critical Temperature for La:21; [La(Sr)-Cu-O]
Critical Temperature (K) |
37.5 |
Measurement Method: Unknown T
c method
No measurement details were noted.
Cautions: Unevaluated Data