Magnetic properties of transition metal dimers probed by inelastic neutron scattering

TL;DR

This study uses Inelastic Neutron Scattering to investigate the magnetic properties and spin dynamics of transition metal dimers, providing detailed insights into their microscopic spin Hamiltonian parameters relevant for spintronic applications.

Contribution

It demonstrates the application of INS to determine spin Hamiltonian parameters of transition metal dimers, revealing complex magnetic behaviors especially in cobalt-based systems.

Findings

Successful determination of microscopic spin Hamiltonian parameters for Ni2.

Observation of complex INS transitions in Co2 indicating intricate magnetic properties.

Deep insight into spin dynamics of transition metal dimers for potential spintronic use.

Abstract

The physical characterisation and understanding of molecular magnetic materials is one of the most important steps towards the integration of such systems in hybrid spintronic devices. Amongst the many characterisation techniques employed in such a task, Inelastic Neutron Scattering (INS) stands as one of the most powerful and sensitive tools to investigate their spin dynamics. Herein, the magnetic properties and spin dynamics of two dinuclear complexes, namely [(M(hfacac)$_2$)$_2$(bpym)] (where M = Ni$^{2+}$, Co$^{2+}$, abbreviated in the following as Ni$_2$, Co$_2$) are reported. These are model systems that could constitute fundamental units of future spintronic devices. By exploiting the highly sensitive IN5 Cold INS spectrometer, we are able to gain a deep insight into the spin dynamics of Ni$_2$ and to fully obtain the microscopic spin Hamiltonian parameters; while for Co$_2$, a multitude of INS transitions are observed demonstrating the complexity of the magnetic properties of octahedral cobalt-based systems.