Anelastic Relaxation of Point Defects in Cubic Crystals

M. Weller
1996 Journal de Physique IV : Proceedings  
Point defects in solids can give rise to anelastic relaxation provided that the defects behave as elastic dipoles. Experiments with single crystals give information on the atomic configuration of the point defects. Measurements of the orientation dependence of the relaxation strength allow determination of the defect symmetry and the dipole shape factor 6h = I h, -A, I . This is demonstrated for two examples: (i) The Snoek relaxation of 0 and N in Nb and Ta single crystals: The 6h values for 0
more » ... he 6h values for 0 and N are in the range of 0.6 to 0.7. The tetragonal defect symmetry is confirmed by experiments on Nb-0 crystals with various orientations. (ii) Defects in cubic, Y20,or CaO-stabilized ZrO,: The oxygen vacancies created for charge compensation are associated with dopant cations thus forming elastic (and electric) dipoles. The dipoles exhibit trigonal symmetry. Article published online by EDP Sciences and available at http://dx.
doi:10.1051/jp4:1996812 fatcat:7e6omd5gjjeb7g4ishvbn4wgim