Coordination-driven magnetic-to-nonmagnetic transition in manganese doped silicon clusters

TL;DR

This study combines experimental and theoretical methods to explore how manganese impurities affect the electronic and magnetic properties of silicon clusters, revealing a transition from magnetic to nonmagnetic states linked to structural changes.

Contribution

It provides new insights into the magnetic behavior of manganese-doped silicon clusters and how local geometric factors influence magnetic states, with implications for bulk silicon defects.

Findings

Structural transition from exohedral to endohedral doping coincides with magnetic quenching.

Magnetic moments depend on manganese coordination number and nearest neighbor distance.

High spin states could be stabilized by lattice expansion.

Abstract

The interaction of a single manganese impurity with silicon is analyzed in a combined experimental and theoretical study of the electronic, magnetic, and structural properties of manganese-doped silicon clusters. The structural transition from exohedral to endohedral doping coincides with a quenching of high-spin states. For all geometric structures investigated, we find a similar dependence of the magnetic moment on the manganese coordination number and nearest neighbor distance. This observation can be generalized to manganese point defects in bulk silicon, whose magnetic moments fall within the observed magnetic-to-nonmagnetic transition, and which therefore react very sensitively to changes in the local geometry. The results indicate that high spin states in manganese-doped silicon could be stabilized by an appropriate lattice expansion.