Magnetic Switching by Oxygen Adsorption in Metal-Organic Framework Systems

TL;DR

This paper models magnetization switching in metal-organic frameworks caused by oxygen adsorption, explaining experimental phenomena through a localized spin model and Monte Carlo simulations.

Contribution

It introduces a simple localized spin model combined with oxygen adsorption dynamics to explain magnetic switching in MOF systems, a novel approach in this context.

Findings

Discontinuous magnetic state changes explained

Magnetic transition temperatures depend on oxygen pressure

Model reproduces experimental transition temperatures

Abstract

In this letter, we address magnetization switching by oxygen adsorption in porous metal-organic framework systems. To this end, we construct a simple localized spin model combined with a Langmuir-type formula for oxygen adsorption and study its finite-temperature properties using Monte Carlo simulation. We successfully explain the main features of this phenomenon, such as the discontinuous changes in magnetic states, sensitivity of the magnetic transition temperatures to oxygen pressure, and absence of singularities in adsorbed oxygen. Based on this model, we also reproduce the observed magnetic transition temperatures for a typical value of oxygen adsorption energy.