Two Series of Microporous Lanthanide-Organic Frameworks with Different Secondary Building Units and Exposed Lewis Base Active Sites: Sensing, Dye Adsorption, and Magnetic Properties.

Two series of new lanthanide complexes, {[Ln(L)(HO)]·DMA·4HO} (1-Ln, Ln = Tb, Gd, and Dy) and {[La(L)]·4HO} (2-La), were prepared successfully by Ln ions and a N-heterocyclic dicarboxylic (2-pyrimidin-5-yl)terephthalic acid (HL) ligand. The four complexes are three-dimensional (3D) microporous frameworks with different secondary building units (SBUs) and exposed Lewis base active sites. Topology analyses reveal that 1-Ln are the binodal (3,8)-connected tfz-d (4)(4·6·8) nets and 2-La is a binodal (2,12)-connected (4)(4·8·12) net. The photoluminescence of 1-Tb, the dye adsorption of 1-Tb and 2-La, and the magnetism of 1-Dy have been well studied. The luminescent explorations indicate that 1-Tb is a highly efficient probe for sensing Fe and CrO, respectively. Complexes 1-Tb and 2-La display the unique selective adsorption to Congo red (CR) dyes. Magnetic measurements further indicate that 1-Dy has a slow magnetic relaxation performance.