Hybridized complexes of [formula omitted] single-molecule magnets and Ni dithiolate complexes

Abstract

The electrochemical oxidation of an acetone solution or acetonitrile (MeCN) solution containing [ Mn III 2 ( 5 -MeOsaltmen ) 2 ( H 2 O ) 2 ] (PF 6) 2 (5-MeOsaltmen 2− = N, N′-(1,1,2,2-tetramethylethylene)bis(5-methoxysalicylideneiminate)) and (NBu 4)[Ni(dmit) 2] (dmit 2− = 2-thioxo-1,3-dithiole-4,5-dithiolate) has yielded two unique hybrid materials in which [Mn 2] 2+ single-molecule magnets (SMMs) possessing an S T = 4 ground state and [Ni(dmit) 2] n− molecules each possessing an average valence of ca.−0.29 are aggregated in a layer-by-layer form; [Mn 2(5-MeOsaltmen) 2(acetone) 2][Ni(dmit) 2] 7 · 4acetone ( 1) and [Mn 2(5-MeOsaltmen) 2(MeCN) 2][Ni(dmit) 2] 7 · 4MeCN ( 2).Compounds 1 and 2 have a similar structure to each other and crystallize in the triclinic P 1 ¯ space group with inversion centers on the midpoint of Mn⋯Mn vector of the dimer and a Ni ion of one of [Ni(dmit) 2] 0.29− molecules (i.e., Z = 1).The [Mn 2] 2+ unit has a typical Mn(III) out-of-plane dimeric core and is structurally consistent with the already reported [Mn 2] SMMs.Seven [Ni(dmit) 2] 0.29− units in the formula have a square-planar coordination geometry in common, and the charge distribution among them can be averagely assigned according to their local structures and IR spectra; thus, the formal charge for each molecule is −0.29.These two kinds of molecules,[Mn 2] 2+ SMM units and [Ni(dmit) 2] 0.29− units, construct hybrid frames aggregating individually, where the latter units form a β-type stacking arrangement. Electronic conductivity measurements revealed that 1 and 2 are semiconductors with σ rt = 1.6 S cm −1 and 2.8 S cm −1, respectively, at room temperature. The detail magnetic measurements proved that the [Mn 2] 2+ units in 1 and 2 behave as S T = 4 SMMs at low temperatures, although their conductivities are already insulated at such temperatures.