Issue 3, 2017

Switchable slow relaxation of magnetization in the native low temperature phase of a cooperative spin-crossover compound

Abstract

The implementation of single-molecule magnet properties in spin crossover materials is sought as a unique source of magnetic multistability at the molecular level. Examples however remain extremely scarce, in part due to the diamagnetic state of most Fe(II) spin crossover materials at low temperatures. We have studied the complex [Fe(mtz)6](CF3SO3)2 (mtz = 1-methyltetrazole) as a tantalizing candidate of such coexistence, due to its known partial spin crossover and therefore paramagnetic native low temperature phase. The single-crystal structures of [Fe(mtz)6](CF3SO3)2 reported here allow rationalizing its peculiar cooperative spin-crossover behavior. Importantly, the high-spin Fe crystallographic sites at low temperature exhibit a high symmetry with a local trigonal distortion, usually source of magnetic anisotropy. The analysis of equilibrium magnetic properties confirm the presence of a significant magnetic anisotropy at the Fe(II) high spin sites in the high symmetry low temperature phase. This results in field-induced slow relaxation of their magnetization which is dominated at low temperature by tunneling and direct processes and is strongly enhanced above 3 K by Raman and Orbach processes. Unprecedentedly, these single-molecule magnet properties are observed in the native ground state of a spin crossover material and efficiently and reversibly switched OFF through visible light irradiation.

Graphical abstract: Switchable slow relaxation of magnetization in the native low temperature phase of a cooperative spin-crossover compound

Supplementary files

Article information

Article type
Edge Article
Submitted
24 Oct 2016
Accepted
09 Dec 2016
First published
19 Dec 2016
This article is Open Access

All publication charges for this article have been paid for by the Royal Society of Chemistry
Creative Commons BY-NC license

Chem. Sci., 2017,8, 2290-2295

Switchable slow relaxation of magnetization in the native low temperature phase of a cooperative spin-crossover compound

A. Urtizberea and O. Roubeau, Chem. Sci., 2017, 8, 2290 DOI: 10.1039/C6SC04737H

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, 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 commercial 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