Short-range forces and the dielectric properties of solid argon

1965 ◽  
Vol 12 (116) ◽  
pp. 393-408 ◽  
Author(s):  
S. Doniach ◽  
R. Huggins
Keyword(s):  
Dielectric Properties ◽  
Short Range ◽  
Solid Argon

NEUTRON DIFFUSE SCATTERING IN LEAD-BASED RELAXOR FERROELECTRICS AND ITS RELATIONSHIP TO THE ULTRA-HIGH PIEZOELECTRICITY

2012 ◽  
Vol 02 (02) ◽  
pp. 1241005 ◽  
Author(s):  
PETER M. GEHRING
Keyword(s):  
Dielectric Properties ◽  
Single Crystal ◽  
Phase Boundary ◽  
Morphotropic Phase Boundary ◽  
Diffuse Scattering ◽  
Short Range ◽  
Piezoelectric Coefficient ◽  
Relaxor Ferroelectrics ◽  
Scattering Measurements

A brief review is presented that summarizes recent neutron diffuse scattering measurements on single crystal PbMg1/3Nb2/3O3 (PMN) and PbZn1/3Nb2/3O3 (PZN) doped with PbTiO3 (PT). Emphasis is placed on results that suggest that the short-range, polar correlations observed in these systems are connected to the anomalous relaxor dielectric properties, and in particular to the large values of the piezoelectric coefficient d33 near the morphotropic phase boundary.

Electronic structure and short-range recombination dynamics of S2 in solid argon

2000 ◽  
Vol 112 (17) ◽  
pp. 7475-7483 ◽  
Author(s):  
Toni Kiljunen ◽  
Jussi Eloranta ◽  
Henrik Kunttu ◽  
Leonid Khriachtchev ◽  
Mika Pettersson ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Short Range ◽  
Solid Argon ◽  
Recombination Dynamics

Low-temperature thermoluminescence in solid argon: Short-range mobility of atoms

1999 ◽  
Vol 111 (4) ◽  
pp. 1650-1657 ◽  
Author(s):  
Leonid Khriachtchev ◽  
Mika Pettersson ◽  
Susanna Pehkonen ◽  
Esa Isoniemi ◽  
Markku Räsänen
Keyword(s):  
Low Temperature ◽  
Short Range ◽  
Solid Argon

Structural dependence of the microwave dielectric properties of Cr3+-substituted ZnGa2O4 spinel ceramics: crystal distortion and vibration mode studies

2019 ◽  
Vol 7 (27) ◽  
pp. 8261-8268 ◽  
Author(s):  
Xiaochi Lu ◽  
Zehui Du ◽  
Bin Quan ◽  
Wenjie Bian ◽  
Haikui Zhu ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Dielectric Properties ◽  
Short Range ◽  
Vibration Mode ◽  
Microwave Dielectric Properties ◽  
Structural Dependence ◽  
Microwave Dielectric ◽  
Short Range Ordering ◽  
Dielectric Performance ◽  
Octahedral Distortion

Establishment of a correlation between the crystal structure (octahedral distortion and short range ordering) and microwave dielectric performance of spinel structured Cr-ZGO.

Schottky Energy Calculations for the Alkali Halides; Details and Results of Successive Approximations

1973 ◽  
Vol 51 (18) ◽  
pp. 1923-1934 ◽  
Author(s):  
I. M. Boswarva ◽  
J. H. Simpson
Keyword(s):  
Dielectric Properties ◽  
Short Range ◽  
Negative Ions ◽  
Alkali Halides ◽  
Successive Approximations ◽  
Point Dipole ◽  
Dielectric Parameters ◽  
Continuum Region ◽  
Region I ◽  
Experimental Values

Results of theoretical determinations of the energy to form a Schottky defect, using a point-dipole model, are presented for alkali halides of the NaCl structure. The calculations were made under the following conditions: (1) Region I (in which the electrostatic and short-range interactions for each ion are treated in detail) contained 6, 18, 26, and 32 ions respectively. (2) Short-range parameters were determined from both the elastic and dielectric properties and the results compared. The "dielectric" parameters produced a better match between the dielectric properties of regions I and II (the dielectric continuum region) and showed better agreement with experimental values for the Schottky energy. (3) Derivations of detailed expressions and calculations were performed independently in two laboratories and cross-checked to eliminate errors.Region I displacements which are presented for the four cases indicate that an instability occurs in the 32-ion case for crystals in which the ions differ considerably in size. An analysis of this problem suggests that a modification of the Born repulsive energy expression is desirable when interaction between negative ions is appreciable.

Raman Imaging and Thermal Expansion of Highly Textured Pb(Mg1/3Nb2/3)O3-PbTiO3 Piezoelectric Ceramics

2004 ◽  
Vol 855 ◽  
Author(s):  
Philippe Colomban ◽  
Mai Pham-Thi
Keyword(s):  
Thermal Expansion ◽  
Dielectric Properties ◽  
Single Crystals ◽  
Short Range ◽  
Low Cost ◽  
Practical Importance ◽  
Production Method ◽  
Raman Imaging ◽  
Textured Ceramics ◽  
The Matrix

ABSTRACTPMN(PZN)-PT single crystals exhibit unique electromechanical properties when oriented and poled along the <001> direction. While expensive crystal growth techniques are advancing slowly, it is of great practical importance to develop an alternative low-cost production method based on strongly oriented or textured ceramics. We present here the thermal expansion, dielectric properties and Raman spectroscopy study of Pb(Mg1/3Nb2/3)O3-PbTiO3 solid solution ((1-x)PMN-xPT, 0.2<x <0.4, here after called PMN xPT) single crystals, random ceramics and ceramics prepared by homo-templated grain growth (HTGG) using cubic PMN-PT single crystal seeds as templates and nanoparticles as ceramic matrix. Representative medium to highly textured ceramics were sintered at 1150°C and 1200°C, respectively, and studied by Raman imaging. Raman peak centre of gravity is used to image the x-composition whereas peak intensity is correlated to the unit-cell distortion and related short-range structure. Smart Raman imaging shows that the final composition is very close to that of the matrix. We compare their thermal expansion (-150 to 300°C) and dielectric properties (R.T. to 300°C) with those of corresponding poled or non-poled single crystals and random ceramics homologues. Short-range ordering and phase diagram are discussed.

Domain coarsening by grain boundary migration in ordered Ni4Mo

1986 ◽  
Vol 44 ◽  
pp. 560-561
Author(s):  
K. Vasudevan ◽  
H. P. Kao ◽  
C. R. Brooks ◽  
E. E. Stansbury
Keyword(s):  
Grain Boundary ◽  
Grain Boundaries ◽  
Short Range ◽  
Boundary Migration ◽  
Grain Boundary Migration ◽  
Rapid Cooling ◽  
Temperature Range ◽  
Fee Structure ◽  
Domain Coarsening ◽  
Boundary Reaction

The Ni4Mo alloy has a short-range ordered fee structure (α) above 868°C, but transforms below this temperature to an ordered bet structure (β) by rearrangement of atoms on the fee lattice. The disordered α, retained by rapid cooling, can be ordered by appropriate aging below 868°C. Initially, very fine β domains in six different but crystallographically related variants form and grow in size on further aging. However, in the temperature range 600-775°C, a coarsening reaction begins at the former α grain boundaries and the alloy also coarsens by this mechanism. The purpose of this paper is to report on TEM observations showing the characteristics of this grain boundary reaction.

Ordering in Ni4Mo by TEM and APFIM

1987 ◽  
Vol 45 ◽  
pp. 214-215
Author(s):  
E.A. Kenik ◽  
T.A. Zagula ◽  
M.K. Miller ◽  
J. Bentley
Keyword(s):  
Electron Irradiation ◽  
Low Temperatures ◽  
Short Range ◽  
Atom Probe ◽  
Range Order ◽  
Considerable Time ◽  
Probe Field ◽  
Disordered Phase ◽  
Transmission Electron ◽  
Diffraction Patterns

The state of long-range order (LRO) and short-range order (SRO) in Ni4Mo has been a topic of interest for a considerable time (see Brooks et al.). The SRO is often referred to as 1½0 order from the apparent position of the diffuse maxima in diffraction patterns, which differs from the positions of the LRO (D1a) structure. Various studies have shown that a fully disordered state cannot be retained by quenching, as the atomic arrangements responsible for the 1½0 maxima are present at temperatures above the critical ordering temperature for LRO. Over 20 studies have attempted to identify the atomic arrangements associated with this state of order. A variety of models have been proposed, but no consensus has been reached. It has also been shown that 1 MeV electron irradiation at low temperatures (∼100 K) can produce the disordered phase in Ni4Mo. Transmission electron microscopy (TEM), atom probe field ion microscopy (APFIM), and electron irradiation disordering have been applied in the current study to further the understanding of the ordering processes in Ni4Mo.

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