Magnetic “Molecular Oligomers” Based on Decametallic Supertetrahedra: A Giant Mn-49 Cuboctahedron and its Mn25Na4 Fragment.

Magnetic “Molecular Oligomers” Based on Decametallic Supertetrahedra: A Giant Mn-49 Cuboctahedron and its Mn25Na4 Fragment.

Two nanosized Mn-49 and Mn25Na4 clusters based on analogues of the high-spin (S=22) [Mn-III Mn-6(II) (4)(mu(4)-O)(4)](18+) supertetrahedral core are reported. Mn-49 and Mn25Na4 complexes consist of eight and four decametallic supertetrahedral subunits, respectively, display high virtual symmetry (Oh), and are unique examples of clusters based on a large number of tightly linked high nuclearity magnetic units. The complexes also have large spin ground-state values (Mn-49: S= 61/2; Mn25Na4: S= 51/2) with the Mn49 cluster displaying single-molecule magnet (SMM) behavior and being the second largest reported homometallic SMM.