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

Abstract

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 = C 2H 5OH and 2-aminopyrimidine (abbreviated as ampym)) are reported. The Mn(II) ions in the compounds [Mn(dca) 2(C 2H 5OH) 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.