A series of 3d-4f heterometallic frameworks comprising 2D lanthanide-organic layers and diverse Cu-complex pillars

Six novel 3D layer-pillared lanthanide-transition metal coordination polymers, LnCuX(IN)₂(Ac)(H₂O) (Ln = Tb, X = Br (1); Ln = Er, X = Cl (2)), [LnCuCl(IN)₂(Ac)]•H₂O (Ln = Gd (3); Ln = Eu (4)), and [LnCu₂Br₂(IN)₂(Ac)(H ₂O)]•nH₂O (Ln = Dy, n =0 (5); Ln = Gd, n = 0.5 (6)) (IN = isonicotinate, Ac = acetate), have been obtained by linking Ln-organic layers and diverse Cu-complex pillars under hydrothermal conditions. 1 and 2 are isostructural and formed by 2D Ln-IN-Ac layers and CuX(IN)₂ pillars (X = Br (1), X= Cl (2)); 3 and 4 are isomorphic and comprised of 2D Ln-IN-Ac layers and dimeric Cu₂Cl(IN)₄ pillars; while 5 and 6 are isostructural and built from 2D Ln-IN-Ac layers and tetrameric Cu ₄Br₄(IN)₄ pillars. The magnetic susceptibility investigation of 3 and 6 shows the presence of weak antiferromagnetic exchange interactions between the Ln³⁺ ions. Compounds 1-6 represent good examples of using 2D Ln-organic layers and diverse Cu-complex pillars as building units to construct intriguing 3D Ln-TM-organic frameworks.