Wydział Chemii

Grażyna Oczko

Przemysław Starynowicz

W. Buda

2012

Polyhedron

46

113-118

10.1016/j.poly.2012.07.044

Naukowa

Angielski

Artykuł

Coordination compounds of a new type, Ln(C₃H₃O₂)₃·xH₂O (where Ln = Nd³⁺, Dy³⁺; C₃H₃O₂⁻ = 2-propenoic anion/acrylic anion, x = 3 or 1.5 for Nd and Dy, respectively), were obtained in crystalline state and their structures were determined. Both crystals are composed of polymeric chains and in both crystals there are two symmetry-independent lanthanide ions, each with a different coordination sphere. The Nd crystal (I) is monoclinic, space group P2₁/c, and the Dy crystal (II) is triclinic, . The Ln³⁺ ions occupy low-symmetry sites in the dimeric structure of Ln(H₂CCHCOO)₃·xH₂O. The spectroscopic investigations of the title monocrystals at room and low temperatures down to 4.2 K were performed to explain the electrostatic nature of the Ln³⁺–ligand bond. Variations in the spectroscopic parameters and their correlations with the nature of the Ln³⁺–L bond are discussed. Analysis of the low-temperature spectra indicates the presence of ion-pair interactions. The influence of the –CC– double bond in the substituent of the carboxylate ions on the distribution of charge, polarity, strength, and character of the Ln–O(L) coordination bond is analysed. The number of electronic components observed in the absorption spectra measured at 4.2 K is compatible with that expected for these systems. Spectroscopic measurements allowed us to compare the optical properties of Ln(H₂CCHCOO)₃·xH₂O with lanthanide acetates and other carboxylates.

lanthanides, 2-propenoic acid, Acrylic acid, UV–Vis spectroscopy, X-ray diffraction

https://doi.org/10.1016/j.poly.2012.07.044

http://www.elsevier.com