Synthesis, Characterization, Thermal Decomposition Mechanism and Properties of the [Eu(4-MOBA)₃(terpy)(H₂O)]₂ Complex

Abstract

A new complex [Eu(4-MOBA)3(terpy) (H2O)]2 (4-MOBA: 4-methoxybenzoate, terpy: 2,2′ :6′ ,2′′terpyridine) was synthesized. The complex was characterized using Fourier transform infrared (FTIR) spectroscopy, elemental analysis, and powder X-ray diffraction (XRD). The structure of the complex was determined using single-crystal XRD. In the complex, each Eu 3+ ion is nine coordinated to one terpy molecule, one water molecule and three carboxylate groups. The carboxylate groups are bonded to the Eu 3+ ion in three modes: bidentate, bridging bidentate, and monodentate. Based on thermogravimetry-differential scanning calorimetry/Fourier transform infrared (TG-DSC/FTIR) measurements, we determined the thermal decomposition mechanism. The emission spectra of the complex exhibited characteristic luminescence, suggesting that terpy and 4-methoxybenzoic acid can act as sensitizing chromophores in this system. Also, bacteriostatic activities for the complex to Candida albicans and Escherichia coli are discussed.