Control of oxidation and spin state in a single-molecule junction

TL;DR

This study demonstrates reversible control of oxidation and spin states in a single Fe-porphyrin molecule using a scanning tunneling microscope, revealing detailed magnetic properties and state evolution.

Contribution

It introduces a method to reversibly manipulate and analyze the oxidation and spin states of a single molecule at the atomic level.

Findings

Reversible control of oxidation and spin states achieved

Magnetocrystalline anisotropy tracked across spin regimes

Density functional and wave function theory support experimental results

Abstract

The oxidation and spin state of a metal-organic molecule determine its chemical reactivity and magnetic properties. Here, we demonstrate the reversible control of the oxidation and spin state in a single Fe-porphyrin molecule in the force field of the tip of a scanning tunneling microscope. Within the regimes of half-integer and integer spin state, we can further track the evolution of the magnetocrystalline anisotropy. Our experimental results are corroborated by density functional theory and wave function theory. This combined analysis allows us to draw a complete picture of the molecular states over a large range of intramolecular deformations.