CRYSTAL STRUCTURE OF {[La2(CNCH2COO)6(H2O)4]H2O}n COMPLEX

Abstract

The lanthanum(III) cyanoacetate complex of formula {[La2(CNCH2COO)6 (H2O)4]∙H2O}n (1), has been prepared and characterized by X-ray diffraction analysis. Compound crystallizes in the triclinic centrosymmetric space group P-1 (No.2), a=8.997(5) Å, b=9.251(5) Å, c=9.728(5) Å, α=67.849(5)°, β=84.224(5)°, γ=81.351(5)°. Single-crystal X-ray diffraction study reveals that crystals of 1 exhibits one-dimensional coordination polymer structure, which is composed of cyanoacetate bridged lanthanum(III) ions. The O9 coordination surrounding of La cation is completed by oxygen atoms of six carboxylate ligands that are coordinated in the bidentate bridging and tridentate-chelating bridging mode and two water molecules. The cations are bridged in a polymeric chain by four exo-bidentate cyanoacetate ligands or through µ2-O function of two other chelato-bridgind cyanoacetate ligands. The La∙∙∙La separation along the polymer is equal to 4.754(3) Å and 4.608(2) Å.

Keywords

• coordination polymers
• lanthanum (III)
• cyanoacetic acid
• crystal structure.