Exploring the transport properties of equatorially low coordinated erbium single ion magnets

Abstract

Single-molecule spin transport represents the lower limit of miniaturization of spintronic devices. These experiments, although extremely challenging, are key to understand the magneto-electronic properties of a molecule in a junction. In this context, theoretical screening of new magnetic molecules provides invaluable knowledge before carrying out sophisticated experiments. Herein, we investigate the transport properties of three equatorially low-coordinated erbium single ion magnets with \(C_{3v}\) symmetry: Er[N(SiMe\(_3\))\(_2\)]\(_3\) (1), Er(btmsm)\(_3\) (2) and Er(dbpc)\(_3\) (3), where btmsm = bis(trimethylsilyl)methyl and dbpc = 2,6-di-tert-butyl-p-cresolate. Our ligand field analysis, based on previous spectroscopic data, confirms a ground state mainly characterized by \(M_J\) =\(\pm\)15/2 in all three of them. The relaxation of their molecular structures when placed between two Au (111) electrodes leads to an even more symmetric \(\sim D_{3h}\) environment, which ensures that these molecules would retain their single-molecule magnet behavior in the device setup. Hence, we simulate spin dependent transport using the DFT optimized structures on the basis of the non-equilibrium Green's function formalism, which, in 1 and 2, suggests a remarkable molecular spin filtering under the effect of an external magnetic field.