A Series of Lanthanide−Transition Metal Frameworks Based on 1-, 2-, and 3D Metal−Organic Motifs Linked by Different 1D Copper(I) Halide Motifs

Hydrothermal reactions of lanthanide(III) oxide and copper halide with isonicotinic acid (Hina) and pyridine-2,3-dicarboxylic acid (H₂pdc) or 1,2-benzenedicarboxylic acid (H₂bdc) lead to three novel lanthanide(III)−copper(I) heterometallic compounds, namely, [Ce₂(ina)₅(na)₂(H₂O)₂][Cu₅Br₄] (1, na = nicotinic acid), [Er₄(ina)₈(bdc)₂(OH)(H₂O)₅][Cu₈I₇] (2), and [Ce₃(ina)₈(bdc)(H₂O)₄][Cu₇Br₆] (3). Compound 1 is constructed from two distinct units of the Ln−organic double chains and inorganic [Cu₅Br₄]_nⁿ⁺ chains. Compound 2 consists of 2D Ln−organic layers and 1D [Cu₈I₇]_nⁿ⁺ cluster chains. Compound 3 can be viewed as a 1D [Cu₆Br₆]_n chainlike motif inserted into the channels of a 3D Ln−Cu−organic motif. Compounds 1−3 exhibit three different 1D inorganic copper(I)−halide chains interconnected with metal−organic 1D chains, 2D layers, and 3D nets resulting in three mixed-motif non-interpenetrating heterometallic Cu−halide−lanthanide (Ln)−organic frameworks, which represent good examples and a facile method to construct such mixed-motif heterometallic compounds. Furthermore, the IR, TGA, and UV−vis spectra of 1−3 were also studied.