Graphitic-BN Based Metal-free Molecular Magnets From A First Principle Study

TL;DR

This study uses first-principles calculations to demonstrate that carbon doping in graphitic boron nitride induces spontaneous magnetization, suggesting potential for metal-free molecular magnets with practical experimental accessibility.

Contribution

It reveals that carbon substitution in graphitic BN induces magnetization and explores its stability in BN nanotubes, advancing the understanding of metal-free magnetic materials.

Findings

Carbon doping induces spontaneous magnetization in BN.

Magnetization originates from carbon 2p electrons.

Magnetization persists in BN nanotubes.

Abstract

We perform a first principle calculation on the electronic properties of carbon doped graphitic boron nitride graphitic BN. It was found that carbon substitution for either boron or nitrogen atom in graphitic BN can induce spontaneous magnetization. Calculations based on density functional theory with the local spin density approximation on the electronic band structure revealed a spin polarized, dispersionless band near the Fermi energy. Spin density contours showed that the magnetization density originates from the carbon atom. The magnetization can be attributed to the carbon 2p electron. Charge density distribution shows that the carbon atom forms covalent bonds with its three nearest neighbourhood. The spontaneous magnetization survives the curvature effect in BN nanotubes, suggesting the possibility of molecular magnets made from BN. Compared to other theoretical models of light-element or metal-free magnetic materials, the carbon-doped BN are more experimentally accessible and can be potentially useful.