Crystal structures and thermodynamic properties of lanthanide complexes with 2,6-dimethylbenzoic acid and 2,2′:6′,2-terpyridine

Two 2D lanthanide coordination polymers Ln(2)(2,6-DMBA)(5)(terpy)(2)(NO3)(H2O)(2) (Ln = La(1), Pr(2); 2,6-D MBA = 2,6-dimethylbenzoic; terpy = 2,2':6',2-terpyridine) were successfully prepared through conventional solution method at room temperature. Their structures were identified by IR, XRD, single crystal X-ray diffraction and elementary analysis. These means show that complexes 1-2 are isomorphous. The two identical central metal ions of the binuclear complex have different coordination environments and coordination numbers. Thermogravimetric analyses (TGA) were researched by TG/DSC-FTIR, and showed multi-step decompositions. The heat capacities of complexes 1 and 2 were determined by DSC from 260.15 K to 374.15 K. Furthermore, based on the fitted polynomial and thermodynamic equation, the thermodynamic parameters values of the complexes 1 and 2 were obtained. (C) 2020 Elsevier Ltd.

Automated summary

Two 2D lanthanide coordination polymers were successfully prepared through conventional solution method, and their structures and thermodynamic properties were identified by various analytical techniques.