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, [Ce ₂(ina)₅(na)₂(H₂O) ₂][Cu₅Br₄] (1, na = nicotinic acid), [Er ₄(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 [Cu₈I ₇]_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.