Abstract
Lanthanide picrate complexes with the ligand N,N,N′,N′‐tetraphenyl‐3,6‐dioxaactanediamide (tdd): [Ln(Pic)~3~(tdd)] (Ln = La, Nd, Eu, Tb, Er) have been prepared in a nonaqueous medium and characterized by elemental analysis, conductivity measurements, IR, and ^1^H‐NMR spectra. The crystal structures of the complexes for Ln = Nd and Er were determined. The early lanthanide, Nd^III^, crystallizes as the nona‐coordinate complex [Nd(Pic)~3~(tdd)]. 2 CH~3~CN in the monoclinic space group __P__2~1~n with a = 11.384(2), b = 18.805(4), c = 27.526(5) Å, β = 99.41(1)°, V = 5832(2) Å^3^, and D~c~ = 1.58 gcm^−3^ for Z = 4. The structure was refined to R = 0.0505, based on 4772 observed Deflections. The late lanthanide, Er^III^, forms an octa‐coordinate complex [Er(Pic)~3~(tdd)]; crystals are triclinic, __P__1, with a = 12.449(2), b = 17.065(2), c = 26.243(4) Å, α = 72.12(1), β = 87.86(1), γ = 84.60(1)°, V = 5282(1) Å^3^, and D~c~ = 1.68 g cm^−3^ for Z, = 4. The structure was refined to R = 0.0469, based on 10666 observed reflections, The results reveal that tdd forms a ring‐like structure with its four O‐atoms, coordinating to the metal ions as multidentate ligand, together with one O‐atom of the bidentate picrate. The structure of the complexes is greatly affected by the ionic radius due to participation of the picrates in coordination.