Enhanced magnetocaloric effect in frustrated magnetic molecules with icosahedral symmetry

TL;DR

This paper explores how geometric frustration in antiferromagnetic molecules with icosahedral symmetry enhances the magnetocaloric effect, leading to high cooling rates near saturation, with comparisons to unfrustrated and other frustrated systems.

Contribution

It demonstrates that icosahedral symmetry in magnetic molecules can produce significant magnetocaloric effects due to unique geometric frustration mechanisms.

Findings

Frustration in corner-sharing triangles enhances magnetocaloric effect.

Large cooling rates observed near saturation field in icosahedral molecules.

Different types of geometric frustration can lead to similar magnetocaloric enhancements.

Abstract

We investigate the magnetocaloric properties of certain antiferromagnetic spin systems that have already been or very likely can be synthesized as magnetic molecules. It turns out that the special geometric frustration which is present in antiferromagnets that consist of corner-sharing triangles leads to an enhanced magnetocaloric effect with high cooling rates in the vicinity of the saturation field. These findings are compared with the behavior of a simple unfrustrated spin ring as well as with the properties of the icosahedron. To our surprise, also for the icosahedron large cooling rates can be achieved but due to a different kind of geometric frustration.