Global ETD Search
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Showing 1 to 6 of 6 for “"Tetragonal Symmetry"”.
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Luminescence of impurity-activated alkali halides under high pressure
… known to occur from an excited state of tetragonal symmetry. In the high pressure CsCI-phase, a similar emission doublet was observed in both In+-and TI+-doped potassium and cesium halides. Again, pressure causes a redistribution of the intensity within the doublet spectrum. A model was …
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Influence of geometric parameters on 3D periodic lattice effective properties
… lattices with cubic, transversely isotropic, and tetragonal symmetry, including an auxetic geometry, over a wide range of relative densities are analyzed within a finite element framework. The effect of geometric parameters on lattice properties is discussed and a comparison between lattices based …
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Anion manipulation in perovskite-related materials
… 12.686(1) Å). Ce\(_2\)MnN\(_3\)F\(_{2-δ}\) with tetragonal symmetry (\(P4/nmm\) \(a\) = 3.8554(4) Å and \(c\) = 13.088(4) Å based on neutron powder diffraction) and a structure related to LaSrMnO\(_4\)F has been synthesised via low-temperature fluorination of the ternary nitride …
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Ladungs- und Orbitalordnungsphänomene in Übergangsmetalloxidverbindungen unter hydrostatischem Druck
… structural transition from an orthorhombic to a tetragonal symmetry is prerequisite for the observation of the ordered state. The cell constructed in this work allows a more exact analysis of the coupling between the crystal lattice and the formation of the charge and spin ordered phase. The …
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Design of quantum well infrared photodetectors
… describing uniaxial strain has the same (tetragonal) symmetry as that describing the confinement of carriers in the quantum wells along the growth direction. Nonuniformity of device parameters across an array of QWIPs is an important issue. High Resolution X-ray Diffraction (HRXRD) was …
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The effect of applied uniaxial stresses on the optical absorption of F centers in alkali halides
… F center excited state to lattice distortions of tetragonal and trigonal symmetry is evaluated. By measuring the third moment change due to the same ~pplied stresses, the separate contributions to the second moment of the F band of dynamic lattice distortions of tetragonal, trigonal, and breathing …