High-Pressure Structural Phase Transition in MgxCd1-xO Compounds

The high-pressure technique is useful to understand physical properties because the technique can directly control bond length and phase transition. As a general trend, the pressure-induced phase transition causes an increase of coordination number with a drastic change of their physical properties. Here, we attempt to explore the pressure-induced phase transitions from the sixfold-coordinated NaCl structure (B1) to the eightfold-coordinated CsCl structure (B2) in MgxCd1−xO by applying an effective interionic interaction potential, which includes the long range Coulomb, van der Waals (vdW) interaction and the short-range repulsive interaction upto second-neighbor ions within the Hafemeister and Flygare approach. Assuming that both the ions are polarizable, the Slater-Kirkwood variational method is employed to estimate the vdW coefficients for parent compounds. The estimated values of the phase transition pressure (Pt) increase with Mg concentration. The vast volume discontinuity in pressure volume phase diagram identifies the structural phase transition from B1 to B2 structure. The results obtain from the present calculations requires the complete understanding of many physical interactions that are essential to ternary oxides, containing elements with size and chemical mismatch, will lead to a consistent explanation of the documented structural properties.

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Theoretical Analysis of the Structural Phase Transformation and Elastic Properties in the ZrN under High Pressure

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.28.101 ◽

2016 ◽

Vol 28 ◽

pp. 101-107

Author(s):

Arvind Jain ◽

Shubhangi Soni ◽

Sanjay Shah ◽

Netram Kaurav

Keyword(s):

Phase Transition ◽

Elastic Properties ◽

Structural Phase Transition ◽

Structural Phase ◽

Repulsive Interaction ◽

Structural Phase Transformation ◽

Interionic Interaction ◽

Cscl Structure ◽

Gibb’S Free Energy ◽

Vdw Interaction

We report a phenomenological model based calculation of pressure-induced structural phase transition and elastic properties of ZrN compound. Gibb’s free energy is obtained as a function of pressure by applying an effective interionic interaction potential, which includes the long range Coulomb, van der Waals (vdW) interaction and the short-range repulsive interaction upto second-neighbor ions within the Hafemeister and Flygare approach. From the present study, we predict a structural phase transition from NaCl structure (B1) to the CsCl structure (B2). 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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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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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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Structural phase transition and photoluminescence properties of wurtzite CdS:Eu3+ nanoparticles under high pressure

RSC Advances ◽

10.1039/c7ra03878j ◽

2017 ◽

Vol 7 (50) ◽

pp. 31433-31440 ◽

Cited By ~ 19

Author(s):

Rui Zhao ◽

Tianye Yang ◽

Yang Luo ◽

Mingyan Chuai ◽

Xiaoxin Wu ◽

...

Keyword(s):

Phase Transition ◽

High Pressure ◽

Structural Phase Transition ◽

Structural Phase ◽

Cds Nanoparticles ◽

Pressure Probe ◽

Photoluminescence Properties ◽

Rocksalt Structure ◽

Phase Transition Pressure ◽

The Eu

Eu dopant increases the phase transition pressure from wurtzite to rocksalt structure compared with CdS nanoparticles. The PL peaks of the Eu3+ ions can used as pressure probe after the quenching of the PL peaks of rocksalt structure CdS.

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BAND STRUCTURE, METALLIZATION, AND SUPERCONDUCTIVITY OF GaAs AND InAs UNDER HIGH PRESSURE

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633607003416 ◽

2007 ◽

Vol 06 (04) ◽

pp. 833-843 ◽

Cited By ~ 2

Author(s):

A. AMALRAJ ◽

C. NIRMALA LOUIS ◽

SR. GERARDIN JAYAM

Keyword(s):

Phase Transition ◽

High Pressure ◽

Band Structure ◽

Structural Phase Transition ◽

Electronic Band Structure ◽

Structural Phase ◽

Normal Structure ◽

Superconducting Transition ◽

Electronic Band ◽

Phase Transition Pressure

The electronic band structure, metallization, structural phase transition, and superconductivity of cubic zinc blende type GaAs and InAs are investigated. The equilibrium lattice constant, bulk modulus, and the phase transition pressure at which the compounds undergo structural phase transition from ZnS to NaCl are predicted from the total energy calculations. The density of states at the Fermi level (N(E F )) get enhanced after metallization, which leads to the superconductivity in GaAs and InAs . The superconducting transition temperatures (T c ) of GaAs and InAs are obtained as a function of pressure for both the ZnS and NaCl structures. GaAs and InAs come under the class of pressure-induced superconductors. When pressure is increased T c increases in both the normal and high pressure-structures. The dependence of T c on electron–phonon mass enhancement factor λ shows that GaAs and InAs are electron–phonon-mediated superconductors. Also, it is found that GaAs and InAs retained in their normal structure under high pressure give appreciably high T c .

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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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High Pressure Structural Phase Transition and Elastic Properties of Europium Chalcogenides

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1047.163 ◽

2014 ◽

Vol 1047 ◽

pp. 163-169

Author(s):

Ashvini K. Sahu ◽

M. Aynyas ◽

R. Bhardwaj ◽

Sankar P. Sanyal

Keyword(s):

Experimental Data ◽

Phase Transition ◽

High Pressure ◽

Elastic Properties ◽

Structural Phase Transition ◽

Structural Phase ◽

Phase Transition Pressure ◽

Ionic Nature ◽

Three Body ◽

Body Potential

The high pressure induced structural phase transition and elastic properties of three Europium chalcogenides (EuX; X = S, Se, Te) have been studied using a two body potential approach. The calculated compression curves of EuS, EuSe and EuTe obtained so has been compared with recently measured three body potential data. The calculated transition pressures are in good agreement with the experimental data. The phase transition pressure for EuS, EuSe and EuTe going from the NaCl phase to CsCl phase have been observed are 22 GPa, 15 GPa, 10 GPa respectively, close the theoretical and experimental data. We have also calculated bulk modulas and second order elastic constants at high pressure which show partly ionic nature of theses compounds. The B1 (NaCl) phase is found to be higher in energy than the B2 (CsCl) phase and more stable at zero pressure.

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High-pressure structural phase transition and metallization in Ga2S3 under non-hydrostatic and hydrostatic conditions up to 36.4 GPa

Journal of Materials Chemistry C ◽

10.1039/d0tc06004f ◽

2021 ◽

Author(s):

Linfei Yang ◽

Jianjun Jiang ◽

Lidong Dai ◽

Haiying Hu ◽

Meiling Hong ◽

...

Keyword(s):

Phase Transition ◽

Raman Spectroscopy ◽

High Pressure ◽

Structural Properties ◽

Structural Phase Transition ◽

First Principles ◽

Theoretical Calculations ◽

Structural Phase

The vibrational, electrical and structural properties of Ga2S3 were explored by Raman spectroscopy, EC measurements, HRTEM and First-principles theoretical calculations under different pressure environments up to 36.4 GPa.

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