Magnetism of High-Symmetry Lanthanide Molecular Complexes with Metalloligands Directing Orientational Attachment to Ag and HOPG Surfaces

Lanthanide complexes LnPt(SAc)42 are single-ion magnetic molecules that have recently been shown to exhibit interesting bulk magnetic properties that can be tuned by varying the central Ln atom and the surrounding ligands. We demonstrated that HoPt(SAc)42 and TbPt(SAc)42 can be adsorbed on crystalline silver and graphite surfaces by electrospray deposition. Their orientation on the surfaces was determined by combining scanning tunneling microscopy and X-ray linear dichroism, and their magnetic moments were measured using X-ray magnetic circular dichroism. Finally, it was inferred that the molecules exhibit distinct magnetic anisotropies, and we studied the influence of the nonmetallic HOPG and the metallic Ag substrates, respectively. It is demonstrated that the Pt(SAc)4 ligands efficiently reduce the interaction of the lanthanide atom with both surfaces, allowing the retention, to some extent, of the magnetic properties of the magnetic center. This can be vital when integrating magnetic molecules in future quantum-based technologies.