Construction of six novel lanthanide complexes supported by 2,4-difluorobenzoic acid and 5,5′-dimethyl-2,2′-bipyridine: Structures, spectroscopies and thermochemical properties

The reaction of 2,4-difluorobenzoic acid (2,4-DFBA) and 5,5'-dimethyl-2,2'-bipyridine (5,5'-DM-2,2'-bipy) with Ln(NO3)(3)center dot 6H(2)O by via slow evaporation generated a series of new binuclear lanthanide complexes, namely, [Ln (2,4-DFBA)(3)(5,5'-DM-2,2'-bipy)(H2O)](2) (Ln = La (1), Pr (2), Nd (3)) and [Ln(2,4-DFBA)3(5,5'-DM-2,2'-bipy)](2)center dot 2H(2)O (Ln = Sm (4), Eu (5), Gd (6)), had been characterized by elemental analysis, IR spectra, Raman spectra and single-crystal X-ray diffraction. Structural determinations demonstrated that all complexes crystallized in Pi space group, triclinic crystal system. The series consisted of two structural types: complexes 1-3 and 4-6 were isostructural, respectively. The TG/DSC-FTIR technique was employed in order to study thermal decomposition of the complexes. Beyond that, the luminescent property and fluorescence lifetime of complex 5 containing Eu(III) had been investigated in detail.

Automated summary

The reaction between 2,4-difluorobenzoic acid and 5,5'-dimethyl-2,2'-bipyridine with Ln(NO3)(3)center dot 6H(2)O via slow evaporation produced a series of new binuclear lanthanide complexes, which were characterized by various techniques. The complexes showed two structural types, and thermal decomposition as well as the luminescent property of one complex containing Eu(III) were studied in detail.