Unusual magnetic property and theoretical analysis of 1D molecular solid [1-(4′-iodobenzyl)-4-aminopyridinium][Ni(mnt)2] (mnt2− = maleonitriledithiolate)

A novel molecular solid, [1-(4′-iodobenzyl)-4-aminopyridinium][Ni(mnt)2] (mnt2− = maleonitriledithiolate), [IBzPyNH2][Ni(mnt)2] (1), has been structurally characterized and its magnetic properties investigated. The Ni(mnt)2- anions and [IBzPyNH2]+ cations of 1 form completely segregated uniform stacking columns with the Ni⋯Ni distances 4.001 Å in the Ni(mnt)2- stacking column through intermolecular Ni⋯S, S⋯S, Ni⋯Ni or π⋯π interactions. The temperature dependences of the magnetic susceptibilities of 1 reveal that 1 exhibits antiferromagnetic interaction (J = −13.8 cm−1) above 100 K and ferromagnetic interaction (J = 5.5 cm−1) below 100 K. The weak ferromagnetism in low temperature may result from spin canting.