Extended three-body-force shell model dynamics of heavier alkali-halide crystals

1978 ◽  
Vol 17 (2) ◽  
pp. 894-906 ◽  
Author(s):  
R. K. Singh ◽  
H. N. Gupta ◽  
M. K. Agrawal
Keyword(s):  
Shell Model ◽  
Alkali Halide ◽  
Body Force ◽  
Model Dynamics ◽  
Alkali Halide Crystals ◽  
Three Body

Extended three-body-force shell-model dynamics of sodium-halide crystals

1976 ◽  
Vol 14 (6) ◽  
pp. 2625-2632 ◽  
Author(s):  
R. K. Singh ◽  
Kanti Chandra
Keyword(s):  
Shell Model ◽  
Body Force ◽  
Model Dynamics ◽  
Three Body

Photoelastic behaviour and interionic potentials in alkali halide crystals

1981 ◽  
Vol 59 (10) ◽  
pp. 1359-1366 ◽  
Author(s):  
Jai Shanker ◽  
T. S. Verma ◽  
A. Cox ◽  
M. J. L. Sangster
Keyword(s):  
Shell Model ◽  
High Frequency ◽  
Alkali Halide ◽  
Dielectric Constants ◽  
Critical Test ◽  
Photoelastic Data ◽  
Comparison Of The Results ◽  
Alkali Halide Crystals ◽  
Derivatives Of ◽  
Photoelastic Behaviour

In order to make a critical test of some recently developed interionic potentials based on the shell model, the photoelastic behaviour of the alkali halide crystals has been investigated. Values of the strain derivatives of the static and high-frequency dielectric constants have been calculated from sets of potentials due to Catlow et al., Sangster et al., and Sangster and Atwood. A comparison of the results obtained with available experimental photoelastic data demonstrates the superiority of the second set of potentials of Catlow et al.

scholarly journals Lattice Dynamical Study of Platinum by Use of van der Waals Three Body Force Shell Model

2020 ◽  
Author(s):  
U C Srivastava
Keyword(s):  
Shell Model ◽  
Body Force ◽  
Present Model ◽  
Van Der Waals ◽  
Dynamical Study ◽  
Stiffness Constant ◽  
Phonon Spectra ◽  
Three Body ◽  
Rigid Shell ◽  
Fcc Structure

In present article author considered the lattice dynamical study of platinum by use of van der Waals three body force shell model [VTBFSM] due to high stiffness constant C11 and C12 . The present model uses with the frequencies of the optical and vibrational branches in the direction [100] and phonon density of states.The study of phonon spectra are important in determining the mechanica1, electrical and thermodynamical properties of elements and their alloys. The present model incorporates the effect of (VWI) and (TBI) into the rigid shell model with fcc structure, operative up to the second neighbors in short range interactions. The available measured data for platinum (Pt) well agrees with our results.

An extended three-body force shell model for the lattice-dynamics of ionic crystals

1976 ◽  
Vol 349 (1658) ◽  
pp. 289-308 ◽  
Keyword(s):  
Shell Model ◽  
Lattice Dynamics ◽  
Significant Contribution ◽  
Body Force ◽  
Cesium Chloride ◽  
Dynamical Matrix ◽  
Ionic Crystals ◽  
Range Overlap ◽  
Dynamical Description ◽  
Three Body

An extended three-body force shell model (e. t. s. m.) for the dynamics of ionic crystals of cesium chloride structure has been developed by reformulating the original t. s. m. The dynamical matrix of the model consists of the long-range Coulomb and three-body interactions and short-range overlap repulsions effective up to the second-neighbours. The off-diagonal elements of this matrix along symmetry directions contain a completely new term having significant contribution for unequal shell charges. The long-wave aspects of e. t. s. m. have been explored to describe the elastic and dielectric behaviour of the crystals. The adequacy of e. t. s. m. to describe the lattice dynamics has been investigated by applying it to the case of thallous bromide (TIBr). The overall agreement between theoretical and experimental results seems to be encouraging and gives some confidence to regard it as an appropriate model for the dynamical description of ionic crystals.

Sign in / Sign up

Export Citation Format

Share Document