Syntheses, crystal structures and magnetic properties of two new ionic pair complexes with well-separated columnar stack structures based on Ni(mnt)_2~-

摘要

The crystal structures of two new ion-pair complexes, [DiClBzPy][Ni(mnt)_2] (1), and [DiClBzQl][Ni(mnt)_2] (2), ([DiClBzPy]~+ = l-(2',4'-dichlorobenzyl)-pyridinium, [DiClBzQl]~+ = l-(2',4'-dichlorobenzyl)-quinolinium, and mnt~(2-) = maleonitriledithiolate) were determined. The Ni(mnt)_2~- anions and cations of 1 and 2 stack into well-segregated columns in the solid state; the Ni(III) ions form a 1D zigzag chain within a Ni(mnt)_2~- column through Ni …S, S…S, Ni…Ni or pi…pi interactions. For 2, the anion-anion, anion-cation and cation-cation contacts play important roles in packing and stabilization. The variable temperature magnetic susceptibilities of 1 and 2 in the 75-298 K range have been interpreted in terms of simple dimer approximation (H = 2JS_AS_B)- The results reveal that both complexes exhibit strong antiferromagnetic interactions with the fitting value g = 2A2 and J = -298.2cm~(-1) for 1, g = 2.17 and /=-218.4cm~(-1) for 2.