LATTICE DYNAMICS OF MgO USING THREE-BODY FORCE SHELL MODEL

A modified three-body force shell model is applied to evaluate the phonon dispersion values of MgO. The many-body interaction in the lattice potential is well accounted for by this theory. The values of the phonon frequencies evaluated by this method are in good confirmation with the neutron spectroscopic data.

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LATTICE DYNAMICS OF TRANSITION METAL OXIDE MnO USING THREE BODY FORCE SHELL MODEL

Modern Physics Letters B ◽

10.1142/s0217984989000200 ◽

1989 ◽

Vol 03 (02) ◽

pp. 115-118 ◽

Cited By ~ 2

Author(s):

S. MOHAN

Keyword(s):

Transition Metal ◽

Metal Oxide ◽

Shell Model ◽

Body Force ◽

Phonon Dispersion ◽

Transition Metal Oxide ◽

Many Body ◽

Experimental Values ◽

Three Body ◽

Many Body Interactions

The phonon dispersion curve for the transition metal oxide viz. manganese oxide at room temperature has been calculated for the first time, assuming Mn ++ and O −− ions are highly polarisable. The three body force shell model employed here takes care of the effect of many body interactions in the lattice potential. The aim of this paper is to treat the various interactions between the ions in a more general way without making them numerically equal. The values of the phonon frequencies evaluated by the new approach are in general, in good agreement with the experimental values.

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Application of the three body force shell model to the lattice dynamics of calcium oxide

Pramana ◽

10.1007/bf02847188 ◽

1973 ◽

Vol 1 (4) ◽

pp. 172-176 ◽

Cited By ~ 7

Author(s):

S K Agarwal ◽

M P Verma

Keyword(s):

Shell Model ◽

Calcium Oxide ◽

Lattice Dynamics ◽

Body Force ◽

Three Body

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Resonance-Assisted Hydrogen Bond—Revisiting the Original Concept in the Context of Its Criticism in the Literature

International Journal of Molecular Sciences ◽

10.3390/ijms23010233 ◽

2021 ◽

Vol 23 (1) ◽

pp. 233

Author(s):

Małgorzata Domagała ◽

Sílvia Simon and Marcin Palusiak

Keyword(s):

Hydrogen Bond ◽

Interaction Energy ◽

Electron Density ◽

Intermolecular Hydrogen Bond ◽

Many Body ◽

Body Interaction ◽

The Many ◽

Three Body ◽

Interaction Approach ◽

Original Concept

In the presented research, we address the original concept of resonance-assisted hydrogen bonding (RAHB) by means of the many-body interaction approach and electron density delocalization analysis. The investigated molecular patterns of RAHBs are open chains consisting of two to six molecules in which the intermolecular hydrogen bond stabilizes the complex. Non-RAHB counterparts are considered to be reference systems. The results show the influence of the neighbour monomers on the unsaturated chains in terms of the many-body interaction energy contribution. Exploring the relation between the energy parameters and the growing number of molecules in the chain, we give an explicit extrapolation of the interaction energy and its components in the infinite chain. Electron delocalization within chain motifs has been analysed from three different points of view: three-body delocalization between C=C-C, two-body hydrogen bond delocalization indices and also between fragments (monomers). A many-body contribution to the interaction energy as well as electron density helps to establish the assistance of resonance in the strength of hydrogen bonds upon the formation of the present molecular chains. The direct relation between interaction energy and delocalization supports the original concept, and refutes some of the criticisms of the RAHB idea.

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

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1976.0074 ◽

1976 ◽

Vol 349 (1658) ◽

pp. 289-308 ◽

Cited By ~ 34

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.

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