| Autor: |
Moreira, R. L., Oliveira, M. A. S., Saint-Gregoire, P., Gesland, J.-Y. |
| Předmět: |
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| Zdroj: |
Ferroelectrics; 2006, Vol. 334 Issue 1, p57-65, 9p, 3 Diagrams, 4 Graphs |
| Abstrakt: |
Czochralski-grown Li 3 ThF 7 single crystals were investigated by X-ray diffraction and polarized optical microscopy. The crystals show an ordered pattern of micro-cracks, which appear just after their growth. Besides the thermal dependence of the lattice parameters from 220 to 520 K, we demonstrate the appearance of strong ferroelastic distortions in the crystals' ab plane below 368 K, accompanied by 90° orthorhombic domains. The micro-cracking pattern is explained through shear stresses generated by the mismatch between the unit-cell parameters of the tetragonal and orthorhombic phases. Alternative pulling directions and Na doping are proposed as possible solutions to reduce or eliminate the micro-crackings. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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