scholarly journals SUPPLEMENT TO TABLES FOR THE RAPID EVALUATION OF THE DEBYE CHARACTERISTIC TEMPERATURE OF CUBIC CRYSTALS FROM ELASTIC CONSTANTS.

1966 ◽  
Author(s):  
Jr, W C Overton ◽  
A F Schuch
Keyword(s):  
Elastic Constants ◽  
Characteristic Temperature ◽  
Rapid Evaluation ◽  
Cubic Crystals ◽  
Debye Characteristic Temperature

ELASTIC PROPERTIES AND DEBYE CHARACTERISTIC TEMPERATURE OF PARTIALLY MELTED YBa2Cu3O7−x SUPERCONDUCTOR

1988 ◽  
Vol 02 (09) ◽  
pp. 1111-1117 ◽  
Author(s):  
D.F. LEE ◽  
K. SALAMA
Keyword(s):  
Debye Temperature ◽  
Elastic Properties ◽  
Elastic Constants ◽  
Tetragonal Phase ◽  
Room Temperature ◽  
Characteristic Temperature ◽  
Shear Moduli ◽  
Debye Characteristic Temperature ◽  
Temperature Range ◽  
Free Material

The quasi-isotropic elastic constants are measured in a 85% dense partially melted YBa 2 Cu 3 C 7−x superconductor in the temperature range 80–300 K. The room temperature values of the longitudinal and shear moduli of the void-free material are found to be 168 and 59 GPa respectively, and no decrease in these constants is observed during the transition from normal to superconducting states. The Debye temperature is found to be 426 K which is comparable to that of the tetragonal phase polycrystalline BaTiO 3 (429 K).

Debye Characteristic Temperatures of Cubic Metals

1972 ◽  
Vol 50 (21) ◽  
pp. 2712-2714 ◽  
Author(s):  
B. S. Semwal ◽  
P. K. Sharma
Keyword(s):  
Shear Modulus ◽  
Numerical Integration ◽  
Elastic Constants ◽  
Characteristic Temperature ◽  
Debye Characteristic Temperature ◽  
Cubic Metals ◽  
Characteristic Temperatures ◽  
Metallic Element ◽  
Elastic Data ◽  
Direct Numerical Integration

The validity of Hill's formulas for the shear modulus of a polycrystalline cubic solid is examined by calculating the Debye characteristic temperature at 0 °K for a number of cubic metals using the measured elastic constants. The results are compared with calorimetric values and the numbers deduced from direct numerical integration of elastic data. Various methods give nearly similar results if the anisotropy of the metallic element is not excessively large.

The crystal dynamics of cuprous halides

1982 ◽  
Vol 60 (11) ◽  
pp. 1589-1594 ◽  
Author(s):  
Manvir S. Kushwaha
Keyword(s):  
Phonon Dispersion ◽  
Characteristic Temperature ◽  
Force Model ◽  
Phonon Dispersion Curves ◽  
Debye Characteristic Temperature ◽  
Zinc Blende ◽  
Crystal Dynamics ◽  
Bond Bending ◽  
Dynamical Description ◽  
Good Agreement

The lattice dynamics of cuprous halides have been thoroughly investigated by means of an 8-parameter bond-bending force model (BBFM), recently developed and applied successfully to study phonons in various II–VI and III–V compound semiconductors having zinc-blende (ZB) structure. The application of BBFM is made to calculate the phonon dispersion relations, phonon density of states, and temperature variation of the Debye characteristic temperature [Formula: see text] of CuCl, CuBr, and CuI. The room-temperature neutron scattering measurements for phonon dispersion curves along three principal symmetry directions and calorimetric experimental data for the Debye characteristic temperature have been used to check the validity of BBFM for the three crystals. The overall good agreement between theoretical and experimental results supports its use as an appropriate model for the dynamical description of ZB crystals.

The dislocations contrast factors of cubic crystals in the Zener constant range between zero and unity

2002 ◽  
Vol 17 (2) ◽  
pp. 104-111 ◽  
Author(s):  
I. C. Dragomir ◽  
T. Ungár
Keyword(s):  
Elastic Constants ◽  
Elastic Anisotropy ◽  
Profile Analysis ◽  
Anisotropy Constant ◽  
Diffraction Peak ◽  
Polycrystalline Materials ◽  
Ionic Crystals ◽  
Strain Anisotropy ◽  
Cubic Crystals ◽  
Lattice Distortions

Diffraction peak profiles broaden due to the smallness of crystallites and the presence of lattice defects. Strain broadening of powders of polycrystalline materials is often anisotropic in terms of the hkl indices. This kind of strain anisotropy has been shown to be well interpreted assuming dislocations as one of the major sources of lattice distortions. The knowledge of the dislocation contrast factors are inevitable for this interoperation. In a previous work the theoretical contrast factors were evaluated for cubic crystals for elastic constants in the Zener constant range 0.5≤Az≤8. A large number of ionic crystals and many refractory metals have elastic anisotropy, Az, well below 0.5. In the present work the contrast factors for this lower anisotropy-constant range are investigated. The calculations and the corresponding peak profile analysis are tested on ball milled PbS and Nb and nanocrystalline CeO2.

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