Thermal properties of CaO and SrO and their B1-B2 phase boundaries: Validity of the quasi-harmonic approximation

Abdallah Qteish; Tariq Ayasrah; Abdullah I. Al-Sharif; Iyad I. Al-Qasir

doi:10.1016/j.physb.2023.414816

Thermal properties of CaO and SrO and their B1-B2 phase boundaries: Validity of the quasi-harmonic approximation

Abdallah Qteish, Tariq Ayasrah, Abdullah I. Al-Sharif, Iyad I. Al-Qasir

Research output: Contribution to journal › Article › peer-review

1 Scopus citations

Abstract

In this paper, we will further confirm that the validity range of the quasi-harmonic approximation (QHA) can be significantly extended by explicitly calculating the Helmholtz free energy over an appropriate volume range. As in the case of MgO, we performed accurate QHA calculations of the thermal properties of the B1 phase of CaO and SrO over a wide temperature range, as well as their B1-B2 phase boundaries in the pressure–temperature space. This finding contradicts a recent conclusion that the QHA is inadequate for CaO, and it is therefore expected to fail for other alkaline-earth oxides containing more polarizable cations. Moreover, the validity range of the QHA is found to be consistent with the bond ionicity in MgO, CaO and SrO.

Original language	English
Article number	414816
Journal	Physica B: Physics of Condensed Matter
Volume	657
DOIs	https://doi.org/10.1016/j.physb.2023.414816
State	Published - May 15 2023
Externally published	Yes

Funding

The authors would like to thank Hazem Abu-Farsakh for fruitful discussions.

Keywords

Ab-initio calculations
Phase boundary
Phonons
Quasi-harmonic approximation
Structural properties
Thermal properties

Access to Document

10.1016/j.physb.2023.414816

Cite this

@article{6c9f0f9789ac4826940af634ff372650,

title = "Thermal properties of CaO and SrO and their B1-B2 phase boundaries: Validity of the quasi-harmonic approximation",

abstract = "In this paper, we will further confirm that the validity range of the quasi-harmonic approximation (QHA) can be significantly extended by explicitly calculating the Helmholtz free energy over an appropriate volume range. As in the case of MgO, we performed accurate QHA calculations of the thermal properties of the B1 phase of CaO and SrO over a wide temperature range, as well as their B1-B2 phase boundaries in the pressure–temperature space. This finding contradicts a recent conclusion that the QHA is inadequate for CaO, and it is therefore expected to fail for other alkaline-earth oxides containing more polarizable cations. Moreover, the validity range of the QHA is found to be consistent with the bond ionicity in MgO, CaO and SrO.",

keywords = "Ab-initio calculations, Phase boundary, Phonons, Quasi-harmonic approximation, Structural properties, Thermal properties",

author = "Abdallah Qteish and Tariq Ayasrah and Al-Sharif, {Abdullah I.} and Al-Qasir, {Iyad I.}",

note = "Publisher Copyright: {\textcopyright} 2023 Elsevier B.V.",

year = "2023",

month = may,

day = "15",

doi = "10.1016/j.physb.2023.414816",

language = "English",

volume = "657",

journal = "Physica B: Physics of Condensed Matter",

issn = "0921-4526",

publisher = "Elsevier",

}

TY - JOUR

T1 - Thermal properties of CaO and SrO and their B1-B2 phase boundaries

T2 - Validity of the quasi-harmonic approximation

AU - Qteish, Abdallah

AU - Ayasrah, Tariq

AU - Al-Sharif, Abdullah I.

AU - Al-Qasir, Iyad I.

PY - 2023/5/15

Y1 - 2023/5/15

N2 - In this paper, we will further confirm that the validity range of the quasi-harmonic approximation (QHA) can be significantly extended by explicitly calculating the Helmholtz free energy over an appropriate volume range. As in the case of MgO, we performed accurate QHA calculations of the thermal properties of the B1 phase of CaO and SrO over a wide temperature range, as well as their B1-B2 phase boundaries in the pressure–temperature space. This finding contradicts a recent conclusion that the QHA is inadequate for CaO, and it is therefore expected to fail for other alkaline-earth oxides containing more polarizable cations. Moreover, the validity range of the QHA is found to be consistent with the bond ionicity in MgO, CaO and SrO.

AB - In this paper, we will further confirm that the validity range of the quasi-harmonic approximation (QHA) can be significantly extended by explicitly calculating the Helmholtz free energy over an appropriate volume range. As in the case of MgO, we performed accurate QHA calculations of the thermal properties of the B1 phase of CaO and SrO over a wide temperature range, as well as their B1-B2 phase boundaries in the pressure–temperature space. This finding contradicts a recent conclusion that the QHA is inadequate for CaO, and it is therefore expected to fail for other alkaline-earth oxides containing more polarizable cations. Moreover, the validity range of the QHA is found to be consistent with the bond ionicity in MgO, CaO and SrO.

KW - Ab-initio calculations

KW - Phase boundary

KW - Phonons

KW - Quasi-harmonic approximation

KW - Structural properties

KW - Thermal properties

UR - http://www.scopus.com/inward/record.url?scp=85150485817&partnerID=8YFLogxK

U2 - 10.1016/j.physb.2023.414816

DO - 10.1016/j.physb.2023.414816

M3 - Article

AN - SCOPUS:85150485817

SN - 0921-4526

VL - 657

JO - Physica B: Physics of Condensed Matter

JF - Physica B: Physics of Condensed Matter

M1 - 414816

ER -

Thermal properties of CaO and SrO and their B1-B2 phase boundaries: Validity of the quasi-harmonic approximation

Abstract

Funding

Keywords

Access to Document

Other files and links

Fingerprint

Cite this