NIST Standard Reference Database 30
Last Update to Data Content: 2002
"The Thermal Expansions of Thoria, Periclase, and Diamond," B.J. Skinner, American Mineralogist, Vol. 42, pp. 39-55 (1957), published by Mineralogical Society of America.Language: English
"Thoria: The sample used in the present study was the one used by Frondel (1955) in his accurate determination of the cell size. A spectrographic analysis by the United States Geological Survey showed Si and Mg to be the major impurities (0.1% - 0.5%) Periclase: The sample of periclase was a colorless single crystal prepared synthetically by the Norton Company. Diamond: The sample of diamond dust used in the present study was a commerical grade with a grain size less than 1.0 µm. It was comprised of chips from a great many diamonds and is the finest fraction obtained from the crushing of many thousands of diamonds from many localities."
"A new high temperature x-ray powder camera has been designed specifically to measure the thermal expansions of minerals from 20 °C to 1000 °C. The camera is a central mount camera, but only those reflections with Bragg angles greater than 45° are recorded. ... All films were measured on a Hilger and Watts Film Measuring Rule #185, ruled to 1.000 mm ± 0.001 mm, and fitted with a sliding vernier ruled to 0.050 mm ± 0.001 mm. Individual measurements could be estimated to 0.02 mm, by interpolation. The x-ray wavelengths used in all calculations were those recommended by Bragg (1947). The stated precisions of measurements in this paper are the standard deviations."
| Axis |
Temperature ( °C ) |
Axis Length ( Å ) |
|---|---|---|
| a | 8.5 | 5.59475 |
| a | 25.0 | 5.59525(10) |
| a | 33.0 | 5.59557 |
| a | 34.1 | 5.59561 |
| a | 103.1 | 5.59812 |
| a | 162.0 | 5.60040 |
| a | 256.2 | 5.60424 |
| a | 343.1 | 5.60802 |
| a | 398.2 | 5.61069 |
| a | 403.0 | 5.61069 |
| a | 404.2 | 5.61090 |
| a | 421.3 | 5.61189 |
| a | 446.0 | 5.61288 |
| a | 495.9 | 5.61542 |
| a | 593.9 | 5.62044 |
| a | 700.0 | 5.62589 |
| a | 787.2 | 5.63050 |
| Axis |
Temperature ( °C ) |
Axis Length ( Å ) |
|---|---|---|
| a | 10.5 | 4.21130 |
| a | 21.0 | 4.21160 |
| a | 25.0 | 4.21168(20) |
| a | 46.5 | 4.21243 |
| a | 76.5 | 4.21360 |
| a | 131.0 | 4.21595 |
| a | 229.5 | 4.22090 |
| a | 320.6 | 4.22576 |
| a | 404.2 | 4.23047 |
| a | 512.0 | 4.23679 |
| a | 601.8 | 4.24195 |
| a | 703.1 | 4.24812 |
| Axis |
Temperature ( °C ) |
Axis Length ( Å ) |
|---|---|---|
| a | 21.5 | 3.56679 |
| a | 25.0 | 3.56680(9) |
| a | 87.2 | 3.56704 |
| a | 157.2 | 3.56745 |
| a | 233.1 | 3.56802 |
| a | 308.5 | 3.56844 |
| a | 377.7 | 3.56934 |
| a | 453.0 | 3.57019 |
| a | 513.3 | 3.57096 |
| a | 584.5 | 3.57187 |
| a | 657.7 | 3.57291 |
| a | 729.2 | 3.57401 |