Unexpectedly super strong paramagnetism of aromatic peptides due to cations

TL;DR

This study reveals that aromatic peptide assemblies exhibit unexpectedly strong paramagnetism in the presence of certain divalent cations, likely due to cation-π interactions involving aromatic rings.

Contribution

It demonstrates a novel magnetic property in peptide assemblies caused by cation-π interactions, expanding understanding of bio-organic magnetic phenomena.

Findings

AYFFF assemblies show super strong paramagnetism with Zn²⁺, Mg²⁺, Cu²⁺

Paramagnetism approaches ferromagnetic susceptibility levels

Cation-π interactions are responsible for magnetic behavior

Abstract

We found that the AYFFF self-assemblies in the chloride solution of some divalent cations ($Zn^{2+}, Mg^{2+},$ and $Cu^{2+}$) display super strong paramagnetism, which may approach the mass susceptibility of ferromagnetism. We attribute the observed super strong paramagnetism to the existence of the aromatic rings, which interact with the cations through cation-{\pi} interaction.