Metallo‐Ligand Based 3d/4f Coordination Polymers: Synthesis, Structure and Magnetic Properties

Abstract Employment of N,N′‐bis(2‐hydroxy‐4‐carboxyphenyl)oxalamide (H 6 L) in Cu 2+ chemistry afforded the mononuclear complex (Et 4 N) 4 [CuL] ⋅ 13H 2 O ( A ) which comprises a square planar [CuL] 4− complex with several O donor atoms in its periphery. The 1 : 1 reaction between complex A and Ln(NO 3 ) 3 ⋅ xH 2 O (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Yb, x=6 or 9) in 1 : 4 mixture of ethanol/water in the presence of excess of KCl yielded two families of isomorphous 3d/4f coordination polymers, namely (Et 4 N) 0.5 [K 0.5 (H 2 O)Ln(H 2 O) 4 (CuL)] ⋅ 3H 2 O [Ln=La( 1 ), Ce( 2 ), Pr( 3 ), Nd( 4 ), Sm( 5 ), Eu( 6 ) and Gd( 7 )] and [K(H 2 O)Ln(H 2 O) 4 (CuL)] ⋅ ⋅6H 2 O [Ln=Tb( 8 ), Dy( 9 ), Ho( 10 ), Er( 11 ) and Yb( 12 )]. The crystal structures of 2 – 4 revealed the presence of 3D coordination polymers while the crystal structure of 9 the presence of a 2D coordination polymer. In both 3d/4f families, complex A retains its original structure and serves as a “metallo‐ligand”. The magnetic properties of 2 – 4 , 7 – 9 , 11 and 12 are discussed.