STM Studies of Isolated Mn12-Ph Single Molecule Magnets

TL;DR

This study uses low temperature STM to analyze isolated Mn12-Ph single-molecule magnets on graphite, revealing inhomogeneous local electronic states and enabling detailed atomic-level magnetic investigations.

Contribution

It provides the first detailed STM characterization of isolated Mn12-Ph molecules, highlighting their electronic inhomogeneity and potential for magneto-metric studies at the single-molecule level.

Findings

Observed strong bias-dependent tunneling currents within molecules

Detected localized metallic behavior in certain regions

Enabled atomic-scale investigation of single molecule magnets

Abstract

We study Mn12O12(C6H5COO)16(H2O)4 (Mn12-Ph) single-molecule magnets on highly ordered pyrolytic graphite (HOPG) using low temperature scanning tunneling microscopy (LT-STM) experiments. We report Mn12-Ph in isolation, resembling single molecules with metallic core atoms and organic outer ligands. The local tunneling current observed within the molecular structure shows a strong bias voltage dependency, which is distinct from that of the HOPG surface. Further, evidence of internal inhomogeneity in the local density of states has been observed with high spatial resolution, and this inhomogeneity appears to be due to localized metallic behavior. These results facilitate magneto-metric studies of single molecule magnets in isolation. As compared to bulk crystal studies, our experiments allow the specific investigation of atomic sites in the molecule.