scholarly journals Role of configurational entropy in the thermodynamics of clusters of point defects in crystalline solids

2005 ◽  
Vol 72 (1) ◽  
Author(s):  
Sumeet S. Kapur ◽  
Manish Prasad ◽  
John C. Crocker ◽  
Talid Sinno
Keyword(s):  
Point Defects ◽  
Configurational Entropy ◽  
Crystalline Solids

Diffusion in Crystalline and Amorphous Solids

1985 ◽  
Vol 57 ◽  
Author(s):  
David Lazarus
Keyword(s):  
Point Defects ◽  
Amorphous Materials ◽  
Essential Role ◽  
Volume Diffusion ◽  
Bulk Diffusion ◽  
Amorphous Solids ◽  
Crystalline Solids ◽  
Simple Point ◽  
Diffusion Mechanisms

AbstractDecades of work by a wide variety of techniques were required to establish unambiguously the essential role of simple – and sometimes not so simple – “point” defects in mediating bulk diffusion in crystalline solids. Amorphous solids present new problems for establishing basic diffusion mechanisms. Most experimental techniques which work well for study of diffusion in crystalline solids are useless for study of amorphous materials because of their inherent nonequilibrium structures. A survey of some current results also gives a strong impression that more complex basic mechanisms than simple point defects may be required to account for volume diffusion in these materials.

Contrast From Point Defects in The Infinitesimal Approximation

1980 ◽  
Vol 38 ◽  
pp. 350-351
Author(s):  
L. J. Sykes ◽  
J. J. Hren
Keyword(s):  
Electron Microscope ◽  
Point Defects ◽  
Broad Class ◽  
Stacking Fault ◽  
Crystalline Solids ◽  
Dislocation Loops ◽  
Analytical Expression ◽  
Stacking Fault Tetrahedra

In electron microscope studies of crystalline solids there is a broad class of very small objects which are imaged primarily by strain contrast. Typical examples include: dislocation loops, precipitates, stacking fault tetrahedra and voids. Such objects are very difficult to identify and measure because of the sensitivity of their image to a host of variables and a similarity in their images. A number of attempts have been made to publish contrast rules to help the microscopist sort out certain subclasses of such defects. For example, Ashby and Brown (1963) described semi-quantitative rules to understand small precipitates. Eyre et al. (1979) published a catalog of images for BCC dislocation loops. Katerbau (1976) described an analytical expression to help understand contrast from small defects. There are other publications as well.

ZERO AND FINITE TEMPERATURE STUDY OF SINGLE FULLERENE CAGES AND CARBON “ONIONS” — GEOMETRY AND SHAPE

1993 ◽  
Vol 07 (29n30) ◽  
pp. 1883-1895 ◽  
Author(s):  
A. MAITI ◽  
C.J. BRABEC ◽  
J. BERNHOLC
Keyword(s):  
Interatomic Potential ◽  
Critical Size ◽  
Tight Binding ◽  
Configurational Entropy ◽  
Electronic Structure Calculations ◽  
Carbon Onions ◽  
Three Body ◽  
Structure Calculations ◽  
Scaling Arguments

Scaling arguments are used to show that above a critical size of several thousand atoms, there is a stability crossover from single to multilayer cages. Conjugate gradient minimization using a classical three-body interatomic potential, as well as tight-binding electronic structure calculations yield ground-state configurations for large fullerene shells that are polyhedral with clearly faceted geometry. The structure, energetics and configurational entropy associated with low-energy defects are calculated and the number of defects estimated as a function of temperature. The role of these thermally generated defects on the shape of large fullerenes is investigated in order to explain the nearly spherical shapes of the newly discovered carbon “onions”.

Role of induced quadrupoles in the simulation of intrinsic point defects in AgCl and NaCl

1993 ◽  
Vol 48 (10) ◽  
pp. 6839-6853 ◽  
Author(s):  
Radha D. Banhatti ◽  
Y. V. G. S. Murti
Keyword(s):  
Point Defects ◽  
Intrinsic Point Defects

scholarly journals Point Defects in InGaN/GaN Core–Shell Nanorods: Role of the Regrowth Interface

Nano Express ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 014005 ◽  
Author(s):  
K Loeto ◽  
G Kusch ◽  
P-M Coulon ◽  
SM Fairclough ◽  
E Le Boulbar ◽  
...  
Keyword(s):  
Point Defects ◽  
Core Shell

Self Diffusion in SiC: the Role of Intrinsic Point Defects

2001 ◽  
Vol 353-356 ◽  
pp. 323-326 ◽  
Author(s):  
Alexander Mattausch ◽  
M. Bockstedte ◽  
Oleg Pankratov
Keyword(s):  
Point Defects ◽  
Intrinsic Point Defects ◽  
Self Diffusion

Point defects and blue LED efficiency: the critical role of indium

2021 ◽  
Author(s):  
Thomas Weatherley ◽  
Wei Liu ◽  
Camille Haller ◽  
Yao Chen ◽  
Duncan T. L. Alexander ◽  
...  
Keyword(s):  
Point Defects ◽  
Critical Role ◽  
Blue Led

Phonons in deformable microporous crystalline solids

2019 ◽  
Vol 234 (7-8) ◽  
pp. 513-527 ◽  
Author(s):  
Bogdan Kuchta ◽  
Filip Formalik ◽  
Justyna Rogacka ◽  
Alexander V. Neimark ◽  
Lucyna Firlej
Keyword(s):  
Periodic Structures ◽  
Structural Transformations ◽  
Crystalline Solids ◽  
Predictive Tool ◽  
Crystalline Materials ◽  
Numerical Tools ◽  
Collective Vibrations ◽  
First Time

Abstract Phonons are quantum elastic excitations of crystalline solids. Classically, they correspond to the collective vibrations of atoms in ordered periodic structures. They determine the thermodynamic properties of solids and their stability in the case of structural transformations. Here we review for the first time the existing examples of the phonon analysis of adsorption-induced transformations occurring in microporous crystalline materials. We discuss the role of phonons in determining the mechanism of the deformations. We point out that phonon-based methodology may be used as a predictive tool in characterization of flexible microporous structures; therefore, relevant numerical tools must be developed.

Sign in / Sign up

Export Citation Format

Share Document