Structural, thermal, and spectral investigations of the lanthanide(III) biphenyl-4,4′-dicarboxylates

Abstract

The lanthanide biphenyl-4,4 0 -dicarboxylates (bpdc) series of the general formulae Ln 2 (bpdc) 3 ÁnH 2 O, where Ln = lanthanides from La(III) to Lu(III); bpdc = C 12 H 5 (COO) 2 2-; n = 4, 5 or 6 have been obtained by the conventional precipitation method. All prepared complexes were characterized by elemental analysis, simultaneous thermal analyses thermogravimetric-differential scanning calorimetry (TG-DSC) and TG-FT-IR, FT-IR, and FTRaman spectroscopy as well as X-ray diffraction patterns measurements. In the whole series of analyzed complexes the bpdc 2-ligand is completely deprotonated. In view of that, four carboxylate oxygen atoms are engaged in the coordination of Ln(III) ions. The synthesized compounds are polycrystalline and insoluble in water. They crystallize in the low symmetry crystal systems, like monoclinic and triclinic. Heating in the air atmosphere resulted in the multi-steps decomposition process, namely endothermic dehydration and strong exothermic decomposition processes. The dehydration process leads to the formation of stable anhydrous Ln 2 bpdc 3 compounds which subsequently decompose to the corresponding lanthanide oxides.

Thermal and spectroscopic (IR, XPS) properties of lanthanide(III) benzene-1,3,5-triacetate complexes

“…1, 2). The anhydrous compounds heated above 300-350°C undergo decomposition where the intermediate products are Ln 2 O 2 CO 3 and the residues are: Ln 2 O 3 or Tb 4 O 7 [30][31][32][33]. The above-mentioned final thermal decomposition products are confirmed by the data included in ICDD.…”

New Coordination Polymers of Selected Lanthanides with 1,2-Phenylenediacetate Linker: Structures, Thermal and Luminescence Properties

“…Previously, we have focused on the hydrothermal synthesis and characterization of lanthanide complexes based on the 1,3-phenylenediacetate ligand [39]. As the continuation of our investigations on lanthanide carboxylates [40][41][42][43][44][45], six novel coordination polymers of selected lanthanide ions (i.e., Pr(III), Sm(III), Eu(III), Tb(III), Dy(III), and Er(III)) with flexible 1,2-phenylenediacetate linker were synthesized and characterized. The compounds were prepared by the solvothermal approach from the N,N′-dimethylformamide medium.…”

Photoactive rare earth complexes for fluorescence tuning and sensing cations (Fe3+) and anions (Cr2O72−)

“…18 Besides, the aromatic polycarboxylates in conjunction with rare earth metals which possess high and variable coordination numbers and exible coordination geometries, leading to the formation of the exotic molecular architectures. 19 In the view of these advantages, adenine and biphenyl-4,4 0 -dicarboxylic acid were selected as the ligands. The X-ray diffraction patterns (Fig.…”