### Abstract

First-principles investigations of the Terbium oxide TbO are performed on structural, elastic, mechanical and thermodynamic properties. The investigations are accomplished by employing full potential augmented plane wave FP-LAPW method framed within density functional theory DFT as implemented in the WIEN2k package. The exchange-correlation energy functional, a part of the total energy functional, is treated through Perdew Burke Ernzerhof scheme of the Generalized Gradient Approximation PBEGGA. The calculations of the ground state structural parameters, like lattice constants a_{0}, bulk moduli B and their pressure derivative B′ values, are done for the rock-salt RS, zinc-blende ZB, cesium chloride CsCl, wurtzite WZ and nickel arsenide NiAs polymorphs of the TbO compound. The elastic constants (C_{11}, C_{12}, C_{13}, C_{33}, and C_{44}) and mechanical properties (Young's modulus Y, Shear modulus S, Poisson's ratio σ, Anisotropic ratio A and compressibility β), were also calculated to comprehend its potential for valuable applications. From our calculations, the RS phase of TbO compound was found strongest one mechanically amongst the studied cubic structures whereas from hexagonal phases, the NiAs type structure was found stronger than WZ phase of the TbO. To analyze the ductility of the different structures of the TbO, Pugh's rule (B/S_{H}) and Cauchy pressure (C_{12}–C_{44}) approaches are used. It was found that ZB, CsCl and WZ type structures of the TbO were of ductile nature with the obvious dominance of the ionic bonding while RS and NiAs structures exhibited brittle nature with the covalent bonding dominance. Moreover, Debye temperature was calculated for both cubic and hexagonal structures of TbO in question by averaging the computed sound velocities.

Original language | English |
---|---|

Pages (from-to) | 709-714 |

Number of pages | 6 |

Journal | Results in Physics |

Volume | 7 |

DOIs | |

Publication status | Published - 2017 |

### Fingerprint

### Keywords

- DFT
- Elastic properties
- TbO
- Thermodynamic properties

### ASJC Scopus subject areas

- Physics and Astronomy(all)

### Cite this

*Results in Physics*,

*7*, 709-714. https://doi.org/10.1016/j.rinp.2017.01.027

**Structural, elastic, mechanical and thermodynamic properties of Terbium oxide : First-principles investigations.** / Al-Qaisi, Samah; Abu-Jafar, M. S.; Gopir, Geri Kibe; Ahmed, R.; Bin Omran, S.; Jaradat, Raed; Dahliah, Diana; Khenata, R.

Research output: Contribution to journal › Article

*Results in Physics*, vol. 7, pp. 709-714. https://doi.org/10.1016/j.rinp.2017.01.027

}

TY - JOUR

T1 - Structural, elastic, mechanical and thermodynamic properties of Terbium oxide

T2 - First-principles investigations

AU - Al-Qaisi, Samah

AU - Abu-Jafar, M. S.

AU - Gopir, Geri Kibe

AU - Ahmed, R.

AU - Bin Omran, S.

AU - Jaradat, Raed

AU - Dahliah, Diana

AU - Khenata, R.

PY - 2017

Y1 - 2017

N2 - First-principles investigations of the Terbium oxide TbO are performed on structural, elastic, mechanical and thermodynamic properties. The investigations are accomplished by employing full potential augmented plane wave FP-LAPW method framed within density functional theory DFT as implemented in the WIEN2k package. The exchange-correlation energy functional, a part of the total energy functional, is treated through Perdew Burke Ernzerhof scheme of the Generalized Gradient Approximation PBEGGA. The calculations of the ground state structural parameters, like lattice constants a0, bulk moduli B and their pressure derivative B′ values, are done for the rock-salt RS, zinc-blende ZB, cesium chloride CsCl, wurtzite WZ and nickel arsenide NiAs polymorphs of the TbO compound. The elastic constants (C11, C12, C13, C33, and C44) and mechanical properties (Young's modulus Y, Shear modulus S, Poisson's ratio σ, Anisotropic ratio A and compressibility β), were also calculated to comprehend its potential for valuable applications. From our calculations, the RS phase of TbO compound was found strongest one mechanically amongst the studied cubic structures whereas from hexagonal phases, the NiAs type structure was found stronger than WZ phase of the TbO. To analyze the ductility of the different structures of the TbO, Pugh's rule (B/SH) and Cauchy pressure (C12–C44) approaches are used. It was found that ZB, CsCl and WZ type structures of the TbO were of ductile nature with the obvious dominance of the ionic bonding while RS and NiAs structures exhibited brittle nature with the covalent bonding dominance. Moreover, Debye temperature was calculated for both cubic and hexagonal structures of TbO in question by averaging the computed sound velocities.

AB - First-principles investigations of the Terbium oxide TbO are performed on structural, elastic, mechanical and thermodynamic properties. The investigations are accomplished by employing full potential augmented plane wave FP-LAPW method framed within density functional theory DFT as implemented in the WIEN2k package. The exchange-correlation energy functional, a part of the total energy functional, is treated through Perdew Burke Ernzerhof scheme of the Generalized Gradient Approximation PBEGGA. The calculations of the ground state structural parameters, like lattice constants a0, bulk moduli B and their pressure derivative B′ values, are done for the rock-salt RS, zinc-blende ZB, cesium chloride CsCl, wurtzite WZ and nickel arsenide NiAs polymorphs of the TbO compound. The elastic constants (C11, C12, C13, C33, and C44) and mechanical properties (Young's modulus Y, Shear modulus S, Poisson's ratio σ, Anisotropic ratio A and compressibility β), were also calculated to comprehend its potential for valuable applications. From our calculations, the RS phase of TbO compound was found strongest one mechanically amongst the studied cubic structures whereas from hexagonal phases, the NiAs type structure was found stronger than WZ phase of the TbO. To analyze the ductility of the different structures of the TbO, Pugh's rule (B/SH) and Cauchy pressure (C12–C44) approaches are used. It was found that ZB, CsCl and WZ type structures of the TbO were of ductile nature with the obvious dominance of the ionic bonding while RS and NiAs structures exhibited brittle nature with the covalent bonding dominance. Moreover, Debye temperature was calculated for both cubic and hexagonal structures of TbO in question by averaging the computed sound velocities.

KW - DFT

KW - Elastic properties

KW - TbO

KW - Thermodynamic properties

UR - http://www.scopus.com/inward/record.url?scp=85011811003&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85011811003&partnerID=8YFLogxK

U2 - 10.1016/j.rinp.2017.01.027

DO - 10.1016/j.rinp.2017.01.027

M3 - Article

AN - SCOPUS:85011811003

VL - 7

SP - 709

EP - 714

JO - Results in Physics

JF - Results in Physics

SN - 2211-3797

ER -