Single-molecule magnets: Structure and properties of [Mn 18O 14(O 2CMe) 18(hep) 4(hepH) 2(H 2O) 2](ClO 4) 2 with spin S = 13

Abstract

The reaction of 2-(hydroxyethyl)pyridine (hepH) with a 2:1 molar mixture of [Mn 3O(O 2CMe) 6(py) 3]ClO 4 and [Mn 3O(O 2CMe) 6(py) 3] in MeCN afforded the new mixed-valent (16Mn III, 2Mn II), octadecanuclear complex [Mn 18O 14(O 2CMe) 18(hep) 4(hepH) 2(H 2O) 2](ClO 4) 2 (1) in 20% yield. Complex 1 crystallizes in the triclinic space group P1. Direct current magnetic susceptibility studies in a 1.0 T field in the 5.0-300 K range, and variable-temperature variable-field dc magnetization studies in the 2.0-4.0 K and 2.0-5.0 T ranges were obtained on polycrystalline samples. Fitting of magnetization data established that complex 1 possesses a ground-state spin of S = 13 and D = -0.18 K. This was ..