A comparative synthetic, magnetic and theoretical study of functional M₄Cl₄ cubane-type Co(II) and Ni(II) complexes.

We describe the synthesis, structures, and magnetochemistry of new M4Cl4 cubane-type cobalt(II) and nickel(II) complexes with the formula [M(μ3-Cl)Cl(HL·S)]4 (1: M = Co; 2: M = Ni), where HL·S represents a pyridyl-alcohol-type ligand with a thioether functional group, introduced to allow subsequent binding to Au surfaces. Dc and ac magnetic susceptibility data of 1 and 2 were modeled with a full spin Hamiltonian implemented in the computational framework CONDON 2.0.

Water oxidation catalyzed by a new tetracobalt-substituted polyoxometalate complex: [{Co4(μ-OH)(H2O)3}(Si2W19O70)]11-.

A new polyoxometalate of earth adundant elements [{Co(4)(μ-OH)(H(2)O)(3)}(Si(2)W(19)O(70))](11-) has been synthesized, characterized and shown to be a water oxidation catalyst. The initial catalytic complex is unstable and slowly undergoes hydrolysis. The hydrolysis products have been isolated and characterized, and their catalytic water oxidation activity is assessed.

A polyoxometalate-based single-molecule magnet with an S = 21/2 ground state.

Ligand modification transforms a polyoxometalate-anchored cubane-type [Mn(III)(3)Mn(IV)O(4)] core into a centrosymmetric [Mn(III)(6)Mn(IV)O(8)] di-cubane cluster, and restores the slow magnetization relaxation characteristics typical for [Mn(4)O(4)] cubane-based single-molecule magnets.

A tetranuclear cobalt(II) chain with slow magnetization relaxation.

A solvothermally derived tetranuclear cobalt(II) complex, [Co(4)(phen)(4)Cl(8)] (phen = phenanthroline), featuring a zig-zag backbone of {Co(μ(2)-Cl)(2)Co} planes, exhibits ferromagnetic exchange and slow relaxation of the magnetization and represents the first Co SMM with a linear core structure.

Switching slow relaxation in a Mn(III)(3)Mn(IV) cluster: an example of grafting single-molecule magnets onto polyoxometalates.

Binding an established single-molecule magnet cluster of distorted cubane type [Mn(III)(3)Mn(IV)O(4)] to the lacunary site of an {alpha-P(2)W(15)} polyoxotungstate scaffold results in a surprising zero-field splitting inversion and the subsequent loss of magnetization bistability.