Abstracts 2004

Abstract of Publication No. 485

Grégory Chaboussant, Reto Basler, Hans-Ulrich Güdel, Stefan Ochsenbein, Andrew Parkin, Simon Parsons, Gopalan Rajaraman, Andreas Sieber, Andrew A. Smith, Grigore A. Timco and Richard E. P. Winpenny
Nickel pivalate complexes: structural variations and magnetic susceptibility and inelastic neutron scattering studies
Dalton Trans. 2758-2766 (2004)      Full Text (PDF)      DOI-Link     

Abstract: The synthesis and structural characterisation of three small nickel(II) cages are reported, all stabilised by pivalate ligands. The magnetic properties of the cages have been studied by a combination of susceptibility measurements and inelastic neutron scattering. For a dinuclear cage, [Ni2(m-OH2)(O2CCMe3)4(HO2CCMe3)4] 1 the ground state is S = 2, with a ferromagnetic exchange interaction between the Ni(II) centres of J = 0.32 meV and DS=2 = –0.09 meV in the ground state. For a tetranuclear heterocubane cage, [Ni4(m3-OMe)4(O2CCMe3)4(MeOH)4] 2, two ferromagnetic exchange interactions are found and an S = 4 ground state observed. While the zero-field splitting of this state cannot be determined unambigiously the most likely value is DS=4 = –0.035 meV. For a tetranuclear nickel butterfly, [Ni4(m3-OH)2(O2CCMe3)6(EtOH)6] 3, three exchange interactions are required, two anti-ferromagnetic and one weakly ferromagnetic; the resulting ground state is S = 0. The data enable us to estimate the zero-field splitting of single Ni(II) ions involved in the cage as Di = +1.0 meV. Both 1 and 2 are therefore expected to be new single molecule magnets.

Last modified: 13.12.11 by Gabriela Frei