title: Ferromagnetic manganese "cubes": from PSII to single-molecule magnets.
abstract: The reaction of Mn(O₂CMe)₂·2H₂O with Me-saoH₂ (Me-saoH₂ = 2-hydroxyphenylethanone oxime) in MeCN forms the complex [Mn(III)₄(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 [Mn(III)₄(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 [Mn(III)₄(Et-sao)₄(Et-saoH)₄] (3) in moderate yields. All three tetrametallic cages exclusively contain Mn(III) centres arranged in a "cube"-like topology, in which the metal centres are connected by -N-O(oximate) 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.
authors.affiliation: School of Chemistry, The University of Edinburgh, West Mains Road, UK EH9 3JJ.
authors.forename: Ross
authors.initials: R
authors.lastname: Inglis
authors.forename: Constantinos C
authors.initials: CC
authors.lastname: Stoumpos
authors.forename: Alessandro
authors.initials: A
authors.lastname: Prescimone
authors.forename: Milosz
authors.initials: M
authors.lastname: Siczek
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Lis
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wernsdorfer
authors.forename: Euan K
authors.initials: EK
authors.lastname: Brechin
authors.forename: Constantinos J
authors.initials: CJ
authors.lastname: Milios
mesh_terms: D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry; D018360:Crystallography, X-Ray; D008280:Magnetics; D008345:Manganese / Q000737:chemistry*; D008968:Molecular Conformation; D045332:Photosystem II Protein Complex / Q000737:chemistry* / Q000378:metabolism
chemical_list: D056831:Coordination Complexes; D045332:Photosystem II Protein Complex; D008345:Manganese