Material Specification for Nd:123; [Nd-Ba-Cu-O]
Process: Solid State Reaction
Notes: "Polycrystalline NdBCO was prepared as pellets of about 2 mm thickness and 10 to 16 mm diameter. A stoichiometric mixture of chemicals (≥99.9%) Nd2O3, BaCO3 and CuO with added acetone was ball-milled in zirconia containers for three times one hour, dried, briefly ball-milled again and then pressed into pellets. These were slowly heated in air to 930 °C, held 40 h at 930 °C, cooled at 10 °C/h to 480 °C, held 24 h at 480 °C, and then cooled to room temperature."
Formula: NdBa2Cu3O6.85
Informal Name: Nd:123
Chemical Family: Nd-Ba-Cu-O
Chemical Class: Oxide
Structure Type: Polycrystalline
Manufacturer: In House
Commercial Name: In House
Production Date:
Lot Number:
Production Form:
Crystallography for Nd:123; [Nd-Ba-Cu-O]
| Crystal System: | |
| Formula Units per Cell: | |
| Space Group: |
|
Cell Parameters
| Phase () |
Temp
K
|
a
Å
|
b
Å
|
c
Å
|
| orthorhom |
20 |
3.876 |
3.913 |
11.753 |
| orthorhom |
220 |
3.890 |
3.919 |
11.791 |
| orthorhom |
390 |
3.894 |
3.934 |
11.825 |
| tetragonal |
540 |
3.924 |
-- |
11.869 |
| tetragonal |
700 |
3.935 |
-- |
11.924 |
| tetragonal |
790 |
3.943 |
-- |
11.960 |
Measurement Method: Neutron diffraction
"By neutron powder diffraction at a wavelength...(of) 1.7012 σ, we have investigated about 10 g of the powder sample...in a vanadium container with a diameter of 8 mm. These room-temperature data were analysed by means of a modified version of the Wiles-Young program... The experiments at high temperatures were performed on a conventional two-axis diffractometer (... (wavelength)=2.330 σ, pyrolithic graphite filter of 6 cm length)... For temperatures up to 800 °C a stainless steel container of 8 mm diameter and 0.5 mm wall thickness was used, which showed no reaction with the powder sample."
Cautions: Evaluated Data
Digitized data were obtained from Figures 3 and 5 of the paper.
Thermal Expansion for Nd:123; [Nd-Ba-Cu-O]
| Phase () |
Temperature Range (°C) |
Axis () |
Thermal Expansion (10-6 K-1) |
| orthorhombic |
20-400 |
a |
12.5(3) |
| orthorhombic |
20-400 |
b |
13.7(4) |
| orthorhombic |
20-400 |
c |
17.2(4) |
| tetragonal |
550-800 |
a |
18.1(6) |
| tetragonal |
550-800 |
b |
|
| tetragonal |
550-800 |
c |
31.2(8) |
| tetragonal |
800- 20 |
a |
12.9(2) |
| tetragonal |
800- 20 |
b |
|
| tetragonal |
800- 20 |
c |
18.7(2) |
Measurement Method: Neutron diffraction
"By neutron powder diffraction at a wavelength...(of) 1.7012 σ, we have investigated about 10 g of the powder sample...in a vanadium container with a diameter of 8 mm. These room-temperature data were analysed by means of a modified version of the Wiles-Young program... The experiments at high temperatures were performed on a conventional two-axis diffractometer (... (wavelength)=2.330 σ, pyrolithic graphite filter of 6 cm length)... For temperatures up to 800 °C a stainless steel container of 8 mm diameter and 0.5 mm wall thickness was used, which showed no reaction with the powder sample."
Cautions: Evaluated Data
