Magnetically hindered chain formation in transition-metal break junctions

TL;DR

This study uses first-principles calculations to show that magnetism hinders the formation of long atomic chains in transition-metal break junctions, explaining why such chains are rarely observed and suggesting they are generally magnetic.

Contribution

It reveals that magnetism softens the binding energy of atomic chains, reducing their formation probability, which is a novel insight into transition-metal break junction behavior.

Findings

Magnetism impedes long chain formation in break junctions.

Magnetic moments soften atomic chain binding energies.

Most transition-metal break junctions likely form magnetic chains.

Abstract

Based on first-principles calculations, we demonstrate that magnetism impedes the formation of long chains in break junctions. We find a distinct softening of the binding energy of atomic chains due to the creation of magnetic moments that crucially reduces the probability of successful chain formation. Thereby, we are able to explain the long standing puzzle why most of the transition-metals do not assemble as long chains in break junctions and provide thus an indirect evidence that in general suspended atomic chains in transition-metal break junctions are magnetic.