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Ferromagnetic manganese “cubes”: from PSII to single-molecule magnets†
Ross Inglis,Alessandro Prescimone,Milosz Siczek,Tadeusz Lis,Wolfgang Wernsdorfer,Euan K. Brechin,Constantinos J. Milios
Dalton Transactions Pub Date : 02/11/2010 00:00:00 , DOI:10.1039/B925248G
Abstract

The reaction of Mn(O2CMe)2·2H2O with Me-saoH2 (Me-saoH2= 2-hydroxyphenylethanone oxime) in MeCN forms the complex [MnIII4(Me-sao)4(Me-saoH)4] (1) in good yields. Replacing Me-saoH2 with Naphth-saoH2 (Naphth-saoH2 = 2-hydroxy-1-napthaldoxime) in the presence of CH3ONa forms the complex [MnIII4(Naphth-sao)4(Naphth-saoH)4] (2) in low yields, while the reaction between Mn(ClO4)2·6H2O, Et-saoH2 (Et-saoH2= 2-hydroxypropiophenone oxime) and NBu4OH in MeCN gives the complex [MnIII4(Et-sao)4(Et-saoH)4] (3) in moderate yields. All three tetrametallic cages exclusively contain MnIII centres arranged in a “cube”-like topology, in which the metal centres are connected by–N–Ooximate groups. The magnetic properties of 1–3 are near identical, revealing the presence of only ferromagnetic interactions between the metal ions leading to high-spin ground states of S = 8. The complexes display frequency dependent out-of-phase signals in ac susceptibility studies and, in the case of 1 single-molecule magnetism has been observed by means of single-crystal hysteresis loop measurements.

Graphical abstract: Ferromagnetic manganese “cubes”: from PSII to single-molecule magnets
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