Syntheses, spectra, crystal structures and magnetic properties of molecular solids based on the M(mnt)2- ion (MÂ =Â Ni, Pt)

Two new ion-pair complexes, [1-(4′-nitrobenzyl)-4-aminopyridinium]-bis(maleonitriledithiolato)nickel ([NO2BzPyNH2][Ni(mnt)2]) (1) and [1-(4′-nitrobenzyl)-4-aminopyridinium]-bis(maleonitriledithiolato)platinum ([NO2BzPyNH2][Pt(mnt)2]) (2) have been characterized structurally and magnetically. An unusual magnetic phase transition around 160 K was observed in 1, and 2 was diamagnetic.