Engineering the magnetic coupling and anisotropy at the molecule–magnetic surface interface in molecular spintronic devices

Abstract

A challenge in molecular spintronics is to control the magnetic coupling between magnetic molecules and magnetic electrodes to build efficient devices. Here we show that the nature of the magnetic ion of anchored metal complexes highly impacts the exchange coupling of the molecules with magnetic substrates. Surface anchoring alters the magnetic anisotropy of the cobalt(II)-containing complex (Co(Pyipa)2), and results in blocking of its magnetization due to the presence of a magnetic hysteresis loop. In contrast, no hysteresis loop is observed in the isostructural nickel(II)-containing complex (Ni(Pyipa)2). Through XMCD experiments and theoretical calculations we find that Co(Pyipa)2 is strongly ferromagnetically coupled to the surface, while Ni(Pyipa)2 is either not coupled or weakly antiferromagnetically coupled to the substrate. These results highlight the importance of the synergistic effect that the electronic structure of a metal ion and the organic ligands has on the exchange interaction and anisotropy occurring at the molecule–electrode interface.

Activating the molecular spinterface

“…Such changes are generally ignored in organic electronics, where the conductive electrode basically represents an infinite reservoir of electrical carriers. Spin transport, in contrast, may be significantly influenced by the spin polarization of the boundary, hybridized, atomic layer of the magnetic material 65 . Hybridization effects able to modify inorganic ferromagnetic materials were reported in 2013 for the Co/zinc methyl phenalenyl ZMP interface 54 (Fig.…”

Models to predict the magnetic properties of single- and multiple-bridged phosphate CuII systems: a theoretical DFT insight

“…[8][9][10][11][12][13][14][15][16][17][18][19][20] Recently it has been reported that phosphonate complexes can be condensed to surfaces to engineer magnetic exchange and anisotropy towards molecular spintronic devices. 21 Many efforts have also been made to understand the magneto structural behaviour of phosphonate-derived materials, with the studies by Zheng, Bellitto and Clearfield being important contributions. [9][10][11]20,22 However fewer studies have been done for phosphate based materials.…”

Introducing Magnetism into 2D Nonmagnetic Inorganic Layered Crystals: A Brief Review from First-Principles Aspects

“…In Figure 6d, a ferrimagnetic substrate was first composed by a single substitution of the Vs. When a ferromagnetic SMM was formed on this substrate, it antiferromagnetically interacted with the host, leading the whole system to become AFM [100]. positioned on the edge of the LTMDs [96].…”