Unique Superparamagnetic-like Behavior Observed in Non-pi-delocalized Nitroxide Diradical Compounds Showing Discotic Liquid Crystalline Phase

Unique Superparamagnetic-like Behavior Observed in Non-pi-delocalized Nitroxide Diradical Compounds Showing Discotic Liquid Crystalline Phase Full article

Journal

Chemistry - A European Journal
ISSN: 0947-6539 , E-ISSN: 1521-3765

Output data

Year: 2018, Volume: 24, Number: 65, Pages: 17293-17302 Pages count : 10 DOI: 10.1002/chem.201803534

Tags

liquid crystals; magnetic properties; magneto-LC effect; nitroxide diradicals; phase transitions

Authors

Takemoto Yusa ¹ , Zaytseva Elena ^1,2,3 , Suzuki Katsuaki ¹ , Yoshioka Naoki ⁴ , Takanishi Yoichi ⁵ , Funahashi Masahiro ⁶ , Uchida Yoshiaki ⁷ , Akita Takuya ⁷ , Park Jayeong ¹ , Sato Shuichi ¹ , Clevers Simon ⁸ , Coquerel Gerard ⁸ , Mazhukin Dmitrii G. ^2,3 , Shimono Satoshi ¹ , Sugiyama Masahito ¹ , Takahashi Hiroki ¹ , Yamauchi Jun ¹ , Tamura Rui ¹

Affiliations

1	(Данные Web of science) Kyoto Univ, Grad Sch Human & Environm Studies, Sakyo Ku, Yoshida Nihonmatsu Cho, Kyoto 6068501, Japan
2	(Данные Web of science) Russian Acad Sci, Siberian Branch, NN Vorozhtsov Novosibirsk Inst Organ Chem, 9 Akad Lavrentieva Ave, Novosibirsk 630090, Russia
3	(Данные Web of science) Novosibirsk State Univ, 2 Pirogova St, Novosibirsk 630090, Russia
4	(Данные Web of science) Keio Univ, Dept Appl Chem, Yokohama, Kanagawa 2238522, Japan
5	(Данные Web of science) Kyoto Univ, Grad Sch Sci, Kyoto 6068502, Japan
6	(Данные Web of science) Kagawa Univ, Dept Adv Mat Sci, Fac Engn, Takamatsu, Kagawa, Japan
7	(Данные Web of science) Osaka Univ, Grad Sch Engn Sci, Toyonaka, Osaka 5608531, Japan
8	(Данные Web of science) Univ Rouen, Normandie Univ, SMS, Crystal Genesis Unit,EA 3233, F-76821 Mont St Aignan, France

A unique superparamagnetic-like behavior and a large "positive magneto-LC effect" were observed in the solid phases and the hexagonal columnar (Col(h)) liquid crystalline (LC) phase, respectively, of novel achiral non-pi-delocalized nitroxide diradical compounds (R,S)-1, which showed polymorphism in the solid phases (solids I and II). The SQUID magnetization measurement revealed that (1) (R,S)-1 containing a small amount of racemic diastereomers (R*,R*)-1 possessed an unusual and large temperature-independent magnetic susceptibility (chi(TIM)>0) component in the original nanocrystalline solid I that was responsible for the observed superparamagnetic-like behavior under low magnetic fields and did not arise from the contamination by extrinsic magnetic metal or metal ion impurities, besides ordinary temperature-dependent paramagnetic susceptibility (chi(para)>0) and temperature-independent diamagnetic susceptibility (chi(dia)<0) components, (2) a large increase in molar magnetic susceptibility (chi(M)) (positive magneto-LC effect) that occurred at the solid I-to-liquid crystal transition upon heating was preserved as an additional chi(TIM) increase in the resulting polymorphic nanocrystalline solid II by cooling, and (3) such unique magnetic phenomena were induced by thermal processing for (R,S)-1 or by adding a small amount of (R*,R*)-1 to (R,S)-1 as the impurity.

Takemoto Y. , Zaytseva E. , Suzuki K. , Yoshioka N. , Takanishi Y. , Funahashi M. , Uchida Y. , Akita T. , Park J. , Sato S. , Clevers S. , Coquerel G. , Mazhukin D.G. , Shimono S. , Sugiyama M. , Takahashi H. , Yamauchi J. , Tamura R.
Unique Superparamagnetic-like Behavior Observed in Non-pi-delocalized Nitroxide Diradical Compounds Showing Discotic Liquid Crystalline Phase

Chemistry - A European Journal. 2018. V.24. N65. P.17293-17302. DOI: 10.1002/chem.201803534 WOS Scopus РИНЦ

Full text from publisher

Published online:	Oct 31, 2018
Published print:	Nov 22, 2018

Web of science	WOS:000451233400019
Scopus	2-s2.0-85055941530
Elibrary	38657461
OpenAlex	W2899381110