Structural and magnetic properties of four layered dicyanamide-based coordination polymers: M{N(CN)2}2(DMSO)2, [M = Mn, Fe, Co, Ni]

The crystal structures and magnetic properties of four μ-(1,5) singly bridging dicyanamide complexes, specifically Mn{N(CN)2}2(DMSO)2 (1), Fe{N(CN)2}2(DMSO)2 (2), Co{N(CN)2}2(DMSO)2 (3), and Ni{N(CN)2}2(DMSO)2 (4), (DMSO=dimethyl sulfoxide) are presented. The compounds are isostructural, in which the MII ions adopt a distorted octahedral geometry, coordinating to four nitrile N atoms of the dicyanamide ligand and to the two DMSO molecules, giving rise to (4,4) pseudo-2D square grid sheets. Magnetic interactions in these materials are via the five atom dicyanamide bridge [NCNCN], which is known to propagate weak magnetic exchange, and the complexes do not undergo long-range ordering down to 2K. Single crystal X-ray diffraction, FTIR spectroscopy, CHN analyses, and SQUID magnetometry were used to characterize these materials.