Two new salts containing bis(maleonitriledithiolate)nickel(III)/copper(II) anion and substituted N,N′-dibenzylpiperidinium: Syntheses, crystal structures and magnetic properties

The preparation, crystal structures and magnetic properties of two novel salts, [DiBzPid][Ni(mnt)2](1) and [DiBzPid]2[Cu(mnt)2](2), where [DiBzPid]+=N,N′-dibenzylpiperidinium and mnt2−=maleonitriledithiolate, are investigated. The Ni(III) ions of 1 form a 1D zigzag alternating chain in a [Ni(mnt)2]− column through intermolecular π⋯π stacking interaction, short C⋯S and C⋯N interactions between the adjacent anions, while the cations(C) and anions(A) of 2 stack into a 1D alternating ⋯CCACCACC⋯ column via C–H⋯N, C–H⋯π hydrogen bonds and π⋯π stacking interactions. Magnetic susceptibility measurements in the temperature range 2–300K show that 1 exhibits a spin-gap transition around 150K with Δ/kb=429.94K, while 2 shows a very weakly ferromagnetic coupling behavior with θ=1.18×10−2K.