Syntheses, crystal structures, and magnetic properties of three 1D chain metal-nitroxide complexes bridged by flexible dicarboxylate anions

摘要

Three new one-dimensional (1D) chain metal-nitroxide complexes {[Cu(NIT4Py) _2(suc)(H _2O)]·3H _2O} _n (1), {[Cd(NIT4Py) _2(suc)(H _2O)] ·[Cd(NIT4Py) _2(suc)(H _2O) _2]·3H _2O} _n (2), and {[Zn(NIT4Py)(glu)(H _2O)] ·H _2O} _n (3) [NIT4Py = 2-(4'-pyridyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide, suc = succinate anion and glu = glutarate anion] were synthesized and structurally characterized. Single-crystal X-ray analyses indicate that the three complexes crystallize in neutral 1D chains in which the metal-nitroxide units are linked by flexible dicarboxylate anions. The succinate anions only adopt trans configuration in complexes 1 and 2, whereas the glutarate anion has gauche/anti conformation in complex 3. Magnetic measurements show that complex 1 exhibits weak antiferromagnetic interactions between the copper ions and the nitroxides.