Heat capacities and thermodynamic properties of a 3D Cu(II) supramolecular complex

Abstract

A 3D supramolecule (H 3 O) 2 [Cu(2,6-pdc) 2 ]ÁH 2 O (pdc = pyridinedicarboxylate) has been solvothermally synthesized and characterized by X-ray powder diffraction and FT-IR spectrum. The thermal decomposition characteristics of the complex were investigated by thermogravimetric analysis, which revealed a three-step mass loss process. The low-temperature molar heat capacities of crystalline (H 3 O) 2 [Cu(2,6-pdc) 2 ]ÁH 2 O were measured by temperature-modulated differential scanning calorimetry for the first time. A phenomenon of glass transition was observed. The thermodynamic parameters such as entropy and enthalpy relative to 298.15 K were calculated based on the above molar heat capacity data.