Tuning the mechanical properties of molecular perovskites by controlling framework distortions via A-site substitution

Kronawitter, Silva M.; Park, Shinjoo; Hallweger, Sebastian A.; Myatt, Emily; Pitcairn, Jem; Cliffe, Matthew J.; Daisenberger, Dominik; Drees, Markus; Kieslich, Gregor

Abstract

Molecular perovskites are important materials in the area of barocalorics, improper ferroelectrics and ferroelastics, where the search for principles that link composition, structure and mechanical properties is a key challenge. Herein, we report the synthesis of a new series of dicyanamide-based molecular perovskites [A]Ni(C2N3)3, where the A-site cation (A+) is a range of alkylated piperidinium cations. We use this new family to explore how A+ cations determine their mechanical response by measuring the bulk modulus (B) – using high-pressure powder X-ray diffraction. Within the series, we find a positive correlation between the network distortions of the pseudocubic [Ni(C2N3)3]− network and B. Furthermore, we show that we can tune framework distortions, and therefore B, by synthesising A-site solid solutions. The applied methodology is a blueprint for linking framework distortions and mechanical properties in network materials and guides us toward principles for designing macroscopic properties via systematic compositional changes in molecular perovskites.

Citation

Kronawitter, S. M., Park, S., Hallweger, S. A., Myatt, E., Pitcairn, J., Cliffe, M. J., Daisenberger, D., Drees, M., & Kieslich, G. (2024). Tuning the mechanical properties of molecular perovskites by controlling framework distortions via A-site substitution. Materials Advances, 5(16), 6440-6445. https://doi.org/10.1039/d4ma00587b

• Journal Article Type: Article
• Acceptance Date: Jul 8, 2024
• Online Publication Date: Jul 8, 2024
• Publication Date: Jul 8, 2024
• Deposit Date: Jul 30, 2024
• Publicly Available Date: Jul 30, 2024
• Journal: Materials Advances
• Electronic ISSN: 2633-5409
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 5
• Issue: 16
• Pages: 6440-6445
• DOI: https://doi.org/10.1039/d4ma00587b
• Public URL: https://nottingham-repository.worktribe.com/output/37320176
• Publisher URL: https://pubs.rsc.org/en/content/articlelanding/2024/ma/d4ma00587b