Work

Mechanisms for collective inversion-symmetry breaking in dabconium perovskite ferroelectrics

Year: 2021

Type: article

Abstract: Dabconium hybrid perovskites include a number of recently-discovered ferroelectric phases with large spontaneous polarisations. The origin of ferroelectric response has been rationalised in general terms in the context of hydrogen bonding, covalency, and strain coupling. Here we use a combination of simple theory, Monte Carlo simulations, and density functional theory calculations to assess the ability of these microscopic ingredients-together with the always-present through-space dipolar coupling-to account for the emergence of polarisation in these particular systems whilst not in other hybrid perovskites. Our key result is that the combination of A-site polarity, preferred orientation along 〈111〉 directions, and ferroelastic strain coupling drives precisely the ferroelectric transition observed experimentally. We rationalise the absence of polarisation in many hybrid perovskites, and arrive at a set of design rules for generating FE examples beyond the dabconium family alone.

Source: Journal of Materials Chemistry C

DOI: 10.1039/d1tc00619c

Authors: Dominic J. W. Allen, Nicholas C. Bristowe, Andrew L. Goodwin, Hamish H.-M. Yeung

Institutions: University of Oxford, Durham University, University of Birmingham

Language: English

Topic: Ferroelectric and Piezoelectric Materials

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Funders: University of Birmingham, Engineering and Physical Sciences Research Council, H2020 European Research Council

Awards: The Complexity Revolution: Exploiting Unconventional Order in Next-Generation Materials Design, Tier 2 Hub in Materials and Molecular Modelling