PRESSURE INDUCED PHASE TRANSITION (B3–B1) AND ELASTIC PROPERTIES OF II–VI ZnSe SEMICONDUCTORS

We evolve an effective interionic interaction potential (EIoIP) to investigate the pressure induced phase transitions from Zinc blende (B3) to Rocksalt (B1) structure in ZnSe semiconductor. The developed potential consists of the long-range Coulomb and three-body interactions (TBI) and the Hafemeister and Flygare type short-range (SR) overlap repulsion extended upto the second neighbor ions and the van der Waals (vdW) interaction. The three-body interactions arise from the electron-shell deformation when the nearest-neighbor ions overlap and has been employed for detailed studies of pressure-induced phase-transition behavior of ZnSe semiconductors. Our calculated value of the phase transition pressure (Pt) is higher and the magnitude of the discontinuity in volume at the transition pressure is consistent with reported data. The variation of second-order elastic constants with pressure resembles that observed in some binary semiconductors. It is inferred that the vdW interaction is effective in obtaining the Debye temperature, Gruneisen parameter, thermal expansion coefficient and compressibility. It is argued that the model with TBI (model II) has yielded somewhat more realistic predictions of the phase-transition and high-pressure behavior as compared to usual two-body potentials (model I) based on phenomenological approach.

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Structural and elastic properties of barium chalcogenides (BaX, X=O, Se, Te) under high pressure

Open Physics ◽

10.2478/s11534-008-0011-7 ◽

2008 ◽

Vol 6 (2) ◽

Cited By ~ 15

Author(s):

Purvee Bhardwaj ◽

Sadhna Singh ◽

Neeraj Gaur

Keyword(s):

Phase Transition ◽

High Pressure ◽

Elastic Constants ◽

Structural Phase ◽

Transition Pressure ◽

Phase Transition Pressure ◽

Cscl Structure ◽

Three Body ◽

Derivatives Of ◽

Good Agreement

AbstractIn the present paper we have investigated the high-pressure, structural phase transition of Barium chalcogenides (BaO, BaSe and BaTe) using a three-body interaction potential (MTBIP) approach, modified by incorporating covalency effects. Phase transition pressures are associated with a sudden collapse in volume. The phase transition pressures and associated volume collapses obtained from TBIP show a reasonably good agreement with experimental data. Here, the transition pressure, NaCl-CsCl structure increases with decreasing cation-to-anion radii ratio. In addition, the elastic constants and their combinations with pressure are also reported. It is found that TBP incorporating a covalency effect may predict the phase transition pressure, the elastic constants and the pressure derivatives of other chalcogenides as well.

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High Pressure Structural Phase Transition and Elastic Properties of MgX (X = S, Se, Te) Semiconducting Compounds

MRS Proceedings ◽

10.1557/proc-987-0987-pp03-14 ◽

2006 ◽

Vol 987 ◽

Author(s):

Dinesh Varshney ◽

Netram Kaurav ◽

Kamal Kumar Choudhary ◽

R. Kinge ◽

R. K. Singh

Keyword(s):

Phase Transition ◽

Structural Phase Transition ◽

Structural Phase ◽

Repulsive Interaction ◽

Interionic Interaction ◽

Phase Transition Pressure ◽

Cscl Type ◽

Semiconducting Compounds ◽

Structural Aspects ◽

Vdw Interaction

AbstractPressure-induced structural aspects of NaCl-type (B1) to CsCl-type (B2) structure in MgX [X = S, Se, Te] semiconductors are presented. An effective interionic interaction potential (EIOP) with long range Coulomb, van der Waals (vdW) interaction and the short-range repulsive interaction upto second-neighbor ions within the Hafemeister and Flygare approach is developed. Particular attention is devoted to evaluate the vdW coefficients following the variational method, as both the cation and the anion are polarizable. Our result on vast volume discontinuity in pressure volume phase diagram identifies the structural phase transition from B1 to B2 structure. The estimated value of the phase transition pressure (Pt) is consistent with results previously published. The variations of elastic constants with pressure follow a systematic trend identical to that observed in others compounds of NaCl type structure family.

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Phase transition in CeSe, EuSe and LaSe under high pressure

Open Physics ◽

10.2478/s11534-007-0037-2 ◽

2007 ◽

Vol 5 (4) ◽

Cited By ~ 4

Author(s):

Sadhna Singh ◽

R. Singh ◽

Atul Gour

Keyword(s):

Phase Transition ◽

High Pressure ◽

Elastic Behavior ◽

Transition Pressure ◽

High Pressure Phase Transition ◽

Phase Transition Pressure ◽

Volume Collapse ◽

Range Overlap ◽

Three Body ◽

Repulsive Forces

AbstractThe high pressure phase transition and elastic behavior of rare earth monoselenides (CeSe, EuSe and LaSe) which crystallize in a NaCl-structure have been investigated using the three body interaction potential (TBIP) approach. These interactions arise due to the electronshell deformation of the overlapping ions in crystals. The TBP model consists of a long range Coulomb, three body interactions and the short range overlap repulsive forces operative up to the second neighboring ions. The authors of this paper estimated the values of the phase transition pressure and the associated volume collapse to be closer than other calculations. Thus, the TBIP approach also promises to predict the phase transition pressure and pressure variations of elastic constants of lanthanide compounds.

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Pressure Induced Structural Phase Transition in InP at Room Temperature

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.28.98 ◽

2016 ◽

Vol 28 ◽

pp. 98-100

Author(s):

Pooja Pawar ◽

Shilpa Kapoor ◽

Sadhna Singh

Keyword(s):

Phase Transition ◽

Structural Phase ◽

Theoretical Data ◽

Effect Of Temperature ◽

Repulsive Interaction ◽

Transition Pressure ◽

Phase Transition Pressure ◽

Realistic Interaction ◽

Range Overlap ◽

Three Body

We have investigated the pressure induced phase transition of InP from ZB to NaCl structure associated by using realistic interaction potential model (RIPM), which is modified by taking effect of temperature. This model consists of coulomb interaction, three body interaction, and short range overlap repulsive interaction up to second nearest neighbour. Phase transition pressure is associated with a sudden collapse in volume showing the incidence of first order phase transition. The phase transition pressure and associated volume collapses obtained from present model show a generally good agreement with the available experimental and theoretical data.

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Structural Phase Transformation in SiC and PtC under Pressure

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.547.79 ◽

2013 ◽

Vol 547 ◽

pp. 79-82

Author(s):

Sadhna Singh ◽

V. Abdul Shukoor ◽

M. Faisal Shareef

Keyword(s):

Phase Transition ◽

Nearest Neighbor ◽

Structural Phase ◽

Body Interaction ◽

First Order Phase Transition ◽

Phase Transition Pressure ◽

Range Overlap ◽

Three Body ◽

Repulsive Forces ◽

First Order Phase

The study of pressure induced structural phase transition of silicon carbide and platinum carbide which crystallize in zinc blende structure (B3), has been carried out using the well described three body interaction potential model (TBIPM). Our present TBIP model consists of long range Coulombic, three body interaction and the short range overlap repulsive forces operative up to next nearest neighbor ions. These materials exhibit a first order phase transition from their ZnS (B3) to NaCl (B1) structure. The phase transition pressure for SiC and PtC are 94.5 GPa and 50GPa respectively.

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Study of Structural, Elastic Properties and their Pressure Dependence in IrN Compound

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.28.16 ◽

2016 ◽

Vol 28 ◽

pp. 16-22 ◽

Cited By ~ 1

Author(s):

Shubhangi Soni ◽

Arvind Jain ◽

Kamal Kumar Choudhary ◽

Netram Kaurav

Keyword(s):

Phase Transition ◽

Theoretical Study ◽

Structural Phase ◽

Elastic Behavior ◽

Interionic Interaction ◽

First Order ◽

Transition Pressure ◽

Zinc Blende ◽

Phase Transition Pressure ◽

Cscl Structure

A theoretical study of the elastic behavior in IrN compound using effective interionic interaction potential is carried out. The estimated values of phase transition pressure and the vast volume discontinuity in pressure-volume (PV) phase diagram indicate the structural phase transition from zinc blende (B3) to CsCl structure (B2). C11, C12 and C44 increase nearly linearly with pressure. At phase transition pressure IrN has shown a discontinuity in second order elastic constants, which is in accordance with the first-order character of the phase transition.

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