A series of 3d–4f heterometallic coordination polymers constructed from size-tunable copper halide clusters and lanthanide-organic motifs

Abstract

A series of three-dimensional (3D) lanthanide–copper coordination polymers, namely [Ln₂(NA)₆Cu₆Br₆(H₂O)₄]·3.5H₂O] [Ln = Sm (1), Eu (2), Tb (3), NA⁻ = nicotinate], [Ln(NA)₂Cu₂Br₂(C₂O₄)_0.5(H₂O)₂]·2H₂O [Ln = Gd (4), Er (5), C₂O₄ = oxalate], [Ln(NA)₂Cu₃Br₃(OAc)(H₂O)] [Ln = Sm (6), Eu (7), Tb (8), OAc = acetate], [Er₂(NA)₆Cu₇Br₇(H₂O)₄]·2H₂O (9) and [Gd(NA)₃Cu₃Cl₃(H₂O)₂]·H₂O (10) have been hydrothermally synthesized and structurally characterized. Compounds 1–3 are constructed from Ln–organic chains and two distinct Cu₄Br₄ clusters possessing a (4¹¹.6⁴)₂(4¹⁴.6⁷)₂(4¹⁸.6¹⁰)(4⁹.6)₂ topology. Compounds 4 and 5 are composed of two-dimensional (2D) Ln–organic layers and cubane-like Cu₄Br₄ clusters possessing a (4³.6⁶.8)(4³)(4⁶.6⁶.8³) topology. Compounds 6–8 can be viewed as the connection between Ln–organic chains and prism-like Cu₆Br₆ clusters with 4,6T50 topology. Compound 9 is constructed by Er–organic chains and dicubane-like Cu₈Br₇ clusters possessing a fluorite (flu) topology. Compound 10 consists of Gd–organic chains and inorganic Cu₃Cl₃ chains with tcj/hc topology. The diversity of the products demonstrates that the auxiliary ligand, pH value, reaction temperature and anion have significant effect on the construction of the structures. Moreover, the photoluminescence of 1–3 and 6–8, and the magnetism of 9 and 10 were investigated.