Synthesis, structure and magnetism of two new polymeric double dicyanamido-bridged Mn(II) compounds

The synthesis, crystal structures, as well as the magnetic properties, of two new 1D polymeric Mn(II) compounds containing the ligand dicyanamide (dca), with the general formula [Mn(II)(dca)2(L)2]n (where L = C2H5OH and 2-aminopyrimidine (abbreviated as ampym)) are reported. The Mn(II) ions in the compounds [Mn(dca)2(C2H5OH)2]n (1), and [Mn(dca)2(ampym)2]n (2) possess an octahedral geometry. The octahedron of (1) is formed by four nitrogen atoms of four different dca molecules with a Mn–N distance of 2.217(2) Å and two oxygen atoms of two trans-ethanol molecules with a Mn–O distance of 2.216(3) Å. The Mn–Mn distance is 7.506 Å. The octahedron of (2) is formed by four nitrogen atoms of four different dca molecules with a Mn–N distance of 2.2193(13) Å and two nitrogen atoms of two trans-ampym molecules with a Mn–N distance of 2.3191(18) Å. The Mn–Mn distance is 7.580 Å.Magnetic susceptibility measurements of (2) revealed that a very weak antiferromagnetic interaction (J = −0.22 cm−1) is present between the metal atoms, as was expected, since the Mn–Mn distance is very large and the magnetic interaction must take place via the dca ligands.

Two new 1D polymeric Mn(II) compounds with the general formula [Mn(II)(dca)2(L)2]n (L = C2H5OH and 2-aminopyrimidine, dca = dicyanamide) are reported. The Mn(II) ions in the polymeric compounds are connected via doubly bridged μ1,5-dca molecules.Figure optionsDownload as PowerPoint slide