Site Selective Spectroscopy and Laser Oscillations of Yb3+ ions in BaF2-SrF2-CaF2 Single Crystals of Solid Solution

Single crystals of a GeO2–TiO2 solid solution with the corresponding composition Ge0.57Ti0.43O2 (germanium titanium tetraoxide) were obtained by devitrification of germania-titania glass at high pressure and temperature. The new compound crystallizes in the rutile structure type (space group P42/mnm), where Ge and Ti share the same position M (site symmetry m.mm), with occupancy values of 0.57 (3) and 0.43 (3), respectively, and one O-atom position (m.2m). The M site is in a sixfold O-atom coordination and, as in the original TiO2 rutile structure, an elongation of the O—M—O bonds along the c-axis direction of the coordination polyhedron and deviation of the angles from 90° lead to a decrease in the coordination symmetry from octahedral to tetragonal. The Ge and Ti atoms are fully disordered in the structure, which indicates that the rutile structure is surprisingly pliant given the differing sizes of the two cations.

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X-ray structure refinement of single crystals of CeB6 and Ce0.75La0.25B6 solid solution grown by the solution method

Journal of the Less Common Metals ◽

10.1016/0022-5088(89)90388-3 ◽

1989 ◽

Vol 146 ◽

pp. 309-318 ◽

Cited By ~ 13

Author(s):

M.K. Blomberg ◽

M.J. Merisalo ◽

M.M. Korsukova ◽

V.N. Gurin

Keyword(s):

Solid Solution ◽

Single Crystals ◽

Solution Method ◽

Structure Refinement ◽

X Ray

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The Effect of Solid Solution Impurities on Dislocation Nucleation in a (001) Mo – 1.5 at.% Ir Single Crystal

Materials Science Forum ◽

10.4028/www.scientific.net/msf.662.85 ◽

2010 ◽

Vol 662 ◽

pp. 85-93

Author(s):

Sergey Dub ◽

Igor Zasimchuk ◽

Leonid Matvienko

Keyword(s):

Mechanical Properties ◽

Solid Solution ◽

Shear Stress ◽

Elastic Modulus ◽

Single Crystal ◽

Single Crystals ◽

Free Volume ◽

Dislocation Nucleation ◽

Initial Portion ◽

G 12

Mechanical properties of (001) Mo and (001) Mo – 1.5 at.% Ir single crystals have been studied by nanoindentation. It has been found that the iridium addition to molybdenum leads to an increase in both hardness and elastic modulus. An abrupt elasto-plastic transition (pop-in) at a depth of about 20 - 40 nm caused by dislocation nucleation in previously dislocation-free volume has been observed in the initial portion of the loading curve. It has shown that the Ir addition essentially affects the dislocation nucleation. Mean shear stress required for the dislocation nucleation increased from 10.8 GPa (G/12) for a Mo single crystal to 18.2 GPa (G/8) for the Mo – 1.5 at% Ir solid solution. Thus, the Ir solution in a Mo single crystal affects not only the resistance to the motion of dislocations (hardness) but the nucleation of them as well. The latter is likely to occur as a result of an increase in the structure perfection of the Mo – 1.5 at% Ir solid solution as compared to the pure Mo single crystal.

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