Cookies

We use cookies to ensure that we give you the best experience on our website. You can change your cookie settings at any time. Otherwise, we'll assume you're OK to continue.

Durham University

Department of Physics

Staff profile

Publication details for Professor Tom Lancaster

Manson, Jamie L., Manson, Zachary E., Sargent, Ashley, Villa, Danielle Y., Etten, Nicole L., Blackmore, William J.A., Curley, Samuel P.M., Williams, Robert C., Brambleby, Jamie, Goddard, Paul A., Ozarowski, Andrew, Wilson, Murray N., Huddart, Benjamin M., Lancaster, Tom, Johnson, Roger D., Blundell, Stephen J., Bendix, Jesper, Wheeler, Kraig A., Lapidus, Saul H., Xiao, Fan, Birnbaum, Serena & Singleton, John (2020). Enhancing easy-plane anisotropy in bespoke Ni(II) quantum magnets. Polyhedron 180: 114379.

Author(s) from Durham

Abstract

We examine the crystal structures and magnetic properties of several S = 1 Ni(II) coordination compounds, molecules and polymers, that include the bridging ligands HF2-, AF62- (A = Ti, Zr) and pyrazine or non-bridging ligands F-, SiF62-, glycine, H2O, 1-vinylimidazole, 4-methylpyrazole and 3-hydroxypyridine. Pseudo-octahedral NiN4F2, NiN4O2 or NiN4OF cores consist of equatorial Ni-N bonds that are equal to or slightly longer than the axial Ni-Lax bonds. By design, the zero-field splitting (D) is large in these systems and, in the presence of substantial exchange interactions (J), can be difficult to discriminate from magnetometry measurements on powder samples. Thus, we relied on pulsed-field magnetization in those cases and employed electron-spin resonance (ESR) to confirm D when J << D. The anisotropy of each compound was found to be easy-plane (D > 0) and range from ≈ 8-25 K. This work reveals a linear correlation between the ratio d(Ni-Lax)/d(Ni-Neq) and D although the ligand spectrochemical properties may also be important. We assert that this relationship allows us to predict the type of magnetocrystalline anisotropy in tailored Ni(II) quantum magnets.