Above-room-temperature ferroelectricity and antiferroelectricity in benzimidazoles
Authors: Reiji Kumai
Kensuke Hatahara
Sachio Horiuchi
Fumitaka Kagawa
Youichi Murakami
Kensuke Kobayashi
Yoshinori Tokura
Journal: Nature Communications (2012)
Discipline: Multidisciplinary
Keywords: imidazole unit; amphoteric molecules; electric polarity; electrically switchable; proton tautomerization
Affiliations: National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8562, Japan. 

Abstract:  The imidazole unit is chemically stable and ubiquitous in biological systems; its proton donor and acceptor moieties easily bind molecules into a dipolar chain. Here we demonstrate that chains of these amphoteric molecules can often be bistable in electric polarity and electrically switchable, even in the crystalline state, through proton tautomerization. Polarization-electric field (P-E) hysteresis experiments reveal a high electric polarization ranging from 5 to 10 μC cm(-2) at room temperature. Of these molecules, 2-methylbenzimidazole allows ferroelectric switching in two dimensions due to its pseudo-tetragonal crystal symmetry. The ferroelectricity is also thermally robust up to 400 K, as is that of 5,6-dichloro-2-methylbenzimidazole (up to ~373 K). In contrast, three other benzimidazoles exhibit double P-E hysteresis curves characteristic of antiferroelectricity. The diversity of imidazole substituents is likely to stimulate a systematic exploration of various structure-property relationships and domain engineering in the quest for lead- and rare-metal-free ferroelectric devices. 

Retracted: No

PubPeer comments:
 These panels from Figs 1B, 2C, 4C, 5B purport to show apoptosis under different conditions by way of FACS plots. There is surprisingly little variation among their 3rd-quadrant hairballs of points cells . ![] , 
 This paper belongs to a set of over 400 papers (as per February 2020) that share very similar Western blots with tadpole-like shaped bands, the same background pattern, and striking similarities in title structures, paper layout, bar graph design, and - in a subset - flow cytometry panels. Despite these similarities, these papers are authored by researchers from different departments and institutes, with almost no overlap in authors. The list of these papers is available here: https: docs.google.com spreadsheets d 1KXqTAyl4j-jVorFPMD2XRpr76LcIKJ0CVyIvRj0exYQ edit?usp=sharing A more detailed description of this set of papers, suspected to all be generated by a common source, a paper mill , can be found here: * https: forbetterscience.com 2020 01 24 the-full-service-paper-mill-and-its-chinese-customers (January 2020) * https: scienceintegritydigest.com 2020 02 21 the-tadpole-paper-mill (February 2020) The same paper mill has been described in these papers: * Jana Christopher - Systematic fabrication of scientific images revealed - FEBS Letters (2018) - https: febs.onlinelibrary.wiley.com doi full 10.1002 1873-3468.13201 * Jennifer A Byrne and Jana Christopher - Digital magic, or the dark arts of the 21st centuryu2014how can journals and peer reviewers detect manuscripts and publications from paper mills? - FEBS Letters (2020) - https: febs.onlinelibrary.wiley.com doi full 10.1002 1873-3468.13747 , 
 Expression of Concern, [10 August 2021] . ----------------------------------------- We, the Publisher and Editor of *Artificial Cells, Nanomedicine, and Biotechnology*, are issuing an Expression of Concern for the following article: Jun Zhao, Xiujuan Du, Meng Wang, Peiyao Yang Juanmei Zhang (2019) Salidroside mitigates hydrogen peroxide-induced injury by enhancement of microRNA-27a in human trabecular meshwork cells. *Artificial Cells, Nanomedicine, and Biotechnology*, 47:1, 1758u20131765, DOI: 10.1080 21691401.2019.1608222 After publication of this article, questions about the scientific integrity of the article content were brought to the Publisher and Editoru2019s attention. We reached out to the authors requesting that they supply information that would confirm the articleu2019s integrity. The authors provided several files in response to our queries, but they were unable to provide the original data in a format which satisfies our requirements to confirm the authenticity of some types of data. In particular, they were unable to provide full western blots, where the molecular weight markers are indicated. Therefore, as we continue to work through the issues raised, we advise readers to interpret the information presented in the article with due caution. The authors have been notified about this Expression of Concern. ,