To be or not to be polar: the ferroelectric and antiferroelectric nematic phases.

Cruickshank, Ewan; Rybak, Paulina; Majewska, Magdalena M.; Ramsay, Shona; Wang, Cheng; Zhu, Chenhui; Walker, Rebecca; Storey, John M.D.; Imrie, Corrie T.; Gorecka, Ewa; Pociecha, Damian

Abstract

We report two new series of compounds that show the ferroelectric nematic, NF, phase in which the terminal chain length is varied. The longer the terminal chain, the weaker the dipole–dipole interactions of the molecules are along the director and thus the lower the temperature at which the axially polar NF phase is formed. For homologues of intermediate chain lengths, between the non-polar and ferroelectric nematic phases, a wide temperature range nematic phase emerges with antiferroelectric character. The size of the antiparallel ferroelectric domains critically increases upon transition to the NF phase. In dielectric studies, both collective ("ferroelectric") and non-collective fluctuations are present, and the "ferroelectric" mode softens weakly at the N–NX phase transition because the polar order in this phase is weak. The transition to the NF phase is characterized by a much stronger lowering of the mode relaxation frequency and an increase in its strength, and a typical critical behavior is observed.

Citation

CRUICKSHANK, E., RYBAK, P., MAJEWSKA, M.M., RAMSAY, S., WANG, C, ZHU, C., WALKER, R., STOREY, J.M.D., IMRIE, C.T., GORECKA, E. and POCIECHA, D. 2023. To be or not to be polar: the ferroelectric and antiferroelectric nematic phases. ACS omega [online], 8(39), pages 36562-36568. Available from: https://doi.org/10.1021/acsomega.3c05884

• Journal Article Type: Article
• Acceptance Date: Aug 30, 2023
• Online Publication Date: Sep 18, 2023
• Publication Date: Oct 3, 2023
• Deposit Date: Sep 25, 2023
• Publicly Available Date: Oct 10, 2023
• Journal: ACS omega
• Electronic ISSN: 2470-1343
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 8
• Issue: 39
• Pages: 36562-36568
• DOI: https://doi.org/10.1021/acsomega.3c05884
• Keywords: Alkyis; Diffraction; Molecules; Phase transitions; Polarization
• Public URL: https://rgu-repository.worktribe.com/output/2086714
• Publisher URL: https://pubs.acs.org/doi/10.1021/acsomega.3c05884
• Additional Information: This article has been published with separate supporting information. This supporting information has been incorporated into a single file on this repository and can be found at the end of the file associated with this output.