Ab-initio study of ABiO3 (A=Ba, Sr, Ca) under high pressure

Andriy Smolyanyuk, Cesare Franchini, Lilia Boeri

Research output: Contribution to journalArticle

Abstract

Using ab-initio crystal structure prediction we study the high-pressure phase diagram of ABiO3 bismuthates (A=Ba, Sr, Ca) in a pressure range up to 100 GPa. All compounds show a transition from the low-pressure perovskite structure to highly distorted, low-symmetry phases at high pressures (PD transition), and remain charge disproportionated and insulating up to the highest pressure studied. The PD transition at high pressures in bismuthates can be understood as a combined effect of steric arguments and of the strong tendency of bismuth to charge-disproportionation. In fact, distorted structures permit to achieve a very efficient atomic packing, and at the same time, to have Bi-O bonds of different lengths. The shift of the PD transition to higher pressures with increasing cation size within the ABiO3 series can be explained in terms of chemical pressure.
LanguageEnglish
JournalPhysical Review / B
StatusSubmitted - 2018

Fingerprint

bismuth
tendencies
low pressure
Bismuth
phase diagrams
cations
crystal structure
Perovskite
shift
Phase diagrams
Cations
symmetry
predictions
Crystal structure
Positive ions
perovskite

Cite this

Ab-initio study of ABiO3 (A=Ba, Sr, Ca) under high pressure. / Smolyanyuk, Andriy; Franchini, Cesare; Boeri, Lilia.

In: Physical Review / B, 2018.

Research output: Contribution to journalArticle

@article{bd9a7fcc2cd04488b3889c38652f0ab7,
title = "Ab-initio study of ABiO3 (A=Ba, Sr, Ca) under high pressure",
abstract = "Using ab-initio crystal structure prediction we study the high-pressure phase diagram of ABiO3 bismuthates (A=Ba, Sr, Ca) in a pressure range up to 100 GPa. All compounds show a transition from the low-pressure perovskite structure to highly distorted, low-symmetry phases at high pressures (PD transition), and remain charge disproportionated and insulating up to the highest pressure studied. The PD transition at high pressures in bismuthates can be understood as a combined effect of steric arguments and of the strong tendency of bismuth to charge-disproportionation. In fact, distorted structures permit to achieve a very efficient atomic packing, and at the same time, to have Bi-O bonds of different lengths. The shift of the PD transition to higher pressures with increasing cation size within the ABiO3 series can be explained in terms of chemical pressure.",
author = "Andriy Smolyanyuk and Cesare Franchini and Lilia Boeri",
year = "2018",
language = "English",
journal = "Physical Review / B",
issn = "1098-0121",
publisher = "American Physical Society",

}

TY - JOUR

T1 - Ab-initio study of ABiO3 (A=Ba, Sr, Ca) under high pressure

AU - Smolyanyuk,Andriy

AU - Franchini,Cesare

AU - Boeri,Lilia

PY - 2018

Y1 - 2018

N2 - Using ab-initio crystal structure prediction we study the high-pressure phase diagram of ABiO3 bismuthates (A=Ba, Sr, Ca) in a pressure range up to 100 GPa. All compounds show a transition from the low-pressure perovskite structure to highly distorted, low-symmetry phases at high pressures (PD transition), and remain charge disproportionated and insulating up to the highest pressure studied. The PD transition at high pressures in bismuthates can be understood as a combined effect of steric arguments and of the strong tendency of bismuth to charge-disproportionation. In fact, distorted structures permit to achieve a very efficient atomic packing, and at the same time, to have Bi-O bonds of different lengths. The shift of the PD transition to higher pressures with increasing cation size within the ABiO3 series can be explained in terms of chemical pressure.

AB - Using ab-initio crystal structure prediction we study the high-pressure phase diagram of ABiO3 bismuthates (A=Ba, Sr, Ca) in a pressure range up to 100 GPa. All compounds show a transition from the low-pressure perovskite structure to highly distorted, low-symmetry phases at high pressures (PD transition), and remain charge disproportionated and insulating up to the highest pressure studied. The PD transition at high pressures in bismuthates can be understood as a combined effect of steric arguments and of the strong tendency of bismuth to charge-disproportionation. In fact, distorted structures permit to achieve a very efficient atomic packing, and at the same time, to have Bi-O bonds of different lengths. The shift of the PD transition to higher pressures with increasing cation size within the ABiO3 series can be explained in terms of chemical pressure.

M3 - Article

JO - Physical Review / B

T2 - Physical Review / B

JF - Physical Review / B

SN - 1098-0121

ER -