Issue 4, 2023

Charge transport and antiferromagnetic ordering in nitroxide radical crystals

Abstract

Nonconjugated radical polymers and small molecules are employed as functional materials in organic electronic devices. Furthermore, the unpaired electrons on these materials have permanent magnetic moments, making these materials promising candidates for organic magnets. Through molecular design, strong antiferromagnetic and ferromagnetic ordering have been achieved in conjugated materials. However, the magnetic properties of nonconjugated radical polymers have only shown weak magnetic interactions among the open-shell sites due to the large mean separation between radicals in typical materials. Here, we have designed, synthesized, and crystalized two open-shell molecules that used molecular engineering to control the assembly of the open-shell sites into a strong antiferromagnetically ordered network. The strong antiferromagnetic interaction is evidenced by a high paramagnetic-to-antiferromagnetic transition temperature of ∼40 K. This high transition temperature was a result of a high spin exchange coupling constant J of about −20 cm−1, which was suggested by both experimental and computed coupling parameters given by the energy difference between high-spin and low-spin broken-symmetry structures. In addition, a single-crystal electrical conductivity of ∼10−3 S m−1 was achieved, which indicated the potential of this material in electronic applications. Therefore, this work provides an insight into a design strategy for radical-based electronic and magnetic materials through proper molecular structure modifications.

Graphical abstract: Charge transport and antiferromagnetic ordering in nitroxide radical crystals

Supplementary files

Article information

Article type
Paper
Submitted
03 Nhl 2022
Accepted
24 Huk 2022
First published
29 Huk 2022

Mol. Syst. Des. Eng., 2023,8, 464-472

Author version available

Charge transport and antiferromagnetic ordering in nitroxide radical crystals

Z. Liang, Y. Tan, S. Hsu, J. F. Stoehr, H. Tahir, A. B. Woeppel, S. Debnath, M. Zeller, L. Dou, B. M. Savoie and B. W. Boudouris, Mol. Syst. Des. Eng., 2023, 8, 464 DOI: 10.1039/D2ME00202G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements