Evaluation of endohedral doping of hydrogenated Si fullerenes as a route to magnetic Si building blocks

TL;DR

This study uses density-functional theory to explore endohedral doping of hydrogenated silicon fullerenes, identifying stable structures that preserve high magnetic moments, which could lead to new magnetic silicon-based nanomaterials.

Contribution

It demonstrates the feasibility of stable MSi20H20 cages with preserved magnetic moments, advancing the design of magnetic silicon nanostructures.

Findings

Small Si16H16 cages cannot encapsulate 3d metal dopants.

Stable MSi20H20 cages with high spin moments are identified.

These structures maintain the dopant’s magnetic properties.

Abstract

Density-functional theory based global geometry optimization is used to scrutinize the possibility of endohedral doping of hydrogenated Si fullerenes as a route to Si nanostructures with high magnetic moments. In contrast to previous suggestions, our unbiased sampling finds the smallest Si16H16 endohedral cage generally too small to encapsulate 3d metal dopant atoms. For the next larger fullerene-like cage though, we identify perfectly symmetric MSi20H20 (M = Co, Ti, V, Cr) cage structures as ground states. These structures conserve the high spin moment of the dopant atom and therewith underscore the potential of this Si nanoform for novel cluster-based materials with unique magnetic properties.