A new gadolinium complex with 1, 3-bis (carboxymethyl) imidazolium chloride ionic liquid: Solvothermal synthesis, structure and magnetic properties.

A new 3D complex namely [Gd 4 (C 7 H 7 N 2 O 4) 6 (H 2 O) 12 ·Cl 6 ·9H 2 O (1) was solvothermally synthesized by using 1,3-bis (carboxymethyl) imidazolium cation as a ligand. Single crystal X-ray analysis reveals that 3D positive charged framework was formed by Gd–O coordination bonds,and Gd3+ ions have two kinds of coordination environments. The free counter Cl− ions and lattice H 2 O locate in cavities of 1 through extensive H-bonds and electrostatic attractions between the Cl−/H 2 O and the positive framework. The thermogravimetric analysis (TGA) shows the organic framework decomposed at temperature above 345 °C, giving the final products Gd 2 O 3. The temperature dependent magnetic susceptibility displays antiferromagnetic interaction at temperature below 15.2 K, once above 15.2 K, compound 1 converts into paramagnetic interaction. The gadolinium-based MOF with 1, 3-bis(carboxymethyl)imidazolium Chloride ionic liquid as ligand has good thermal stability and magnetic property. There is Neel temperature at 15.2 K in compound 1 when study its magnetic, at temperature below 15.2 K there is antiferromagnetic interaction, but at temperature above 15.2 K, it converts into paramagnetic interaction. Image 1 1. This structure has 3D positive charged framework was formed by Gd−O coordination bonds. 2. There are free counter Cl− ions and lattice H 2 O locate in cavities of 1 through extensive H−bonds and electrostatic attractions between the Cl−/H 2 O and the positive framework. 3. The organic framework can be kept stables until 345 °C. There are antiferromagnetic interaction in Gd3+ ions at temperature below 15.2 K, once above 15.2 K, they converts into paramagnetic interaction. [ABSTRACT FROM AUTHOR]