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Two cationic heterometal–organic frameworks (Eu-Zn (1·NO3−) and Tb-Zn (2·NO3−)) with NO3− counter-anions in the channels are structurally and luminously characterized. Both of them can serve as highly sensitive and highly selective luminescent probes for detecting I− ions in aqueous solutions. In particular, 2·NO3− can selectively and reversibly detect I− with a fast response time of just 10 s and an extremely low detection limit of 0.001 ppm. Mechanism studies reveal that I− is quickly oxidized to form I3− with the help of 1·NO3− or 2·NO3−, leading to luminescence quenching. This represents the first report of MOF-based luminescent probes for the detection of I− in aqueous solutions. [ABSTRACT FROM AUTHOR]

In this work, one novel three dimensional non-interpenetrated metal–organic framework {[Mn 3 (L) 2 (H 2 O) 4 ]·2H 2 O·2DMF} n ( 1 ) was synthesized by a new tri-carboxylic ligand (H 3 L = 3,5-Bis-[2-(4-carboxy-phenoxy)-ethoxy]-benzoic acid). Single crystal structural determination revealed that compound 1 possesses a stable 3D framework, containing linear tri-nuclear [Mn 3 ] cluster as a node. The investigation on PXRD patterns in various solvents and TGA displays excellent solvents and thermal stability. Additionally, magnetic measurements indicate that antiferromagnetic interactions exist within compound 1 . [ABSTRACT FROM AUTHOR]

Two 3D heterometal-organic frameworks based on infrequent trigonal bipyramidal Ln5 clusters as nodes were structurally and magnetically characterized (Ln=Gd ( 1), Dy ( 2)). The results indicate large MCE of up to 30.7 J kg−1 K−1 in 1 and slow magnetic relaxation behavior in 2. Expectedly, constructing 3D MOFs based on multinuclear clusters as nodes may will be a new strategy for achieving large −Δ Sm. Additionally, compound 1 exhibits high thermal and solvent stabilities, providing a favorable foundation for realistic applications. [ABSTRACT FROM AUTHOR]

Ten new 3D lanthanide-based compounds, {[Ln4(CPOA)6(H2O)4]·H2O}n(Ln = Eu (1), Gd (2), Tb (3), Dy (4), Ho (5))and [Ln(CPOA)(C2O4)0.5(H2O)]n(Ln = Eu (1a), Gd (2a), Tb (3a), Dy (4a), Ho (5a)) (CPOA2–= 4-carbomethoxybenzoate),have been synthesized by a hydrothermal method under different temperatures.The compounds 1–5were obtained at140 °C. When the temperature went up to 180 °C, the ligandspartly decomposed to C2O42–, then came into being compounds 1a–5a. The two series of compounds displayed the differences not onlyin structure but also in thermal stability and luminescent and magneticproperties. Compounds 1–5crystallizein the triclinic system, space group P1̅, whereascompounds 1a–5abelong to the monoclinicsystem with space group P21/c. Thermal analyses were carried out on 1–5and 1a–3a. Solid luminescencestudies of compounds 1and 1a, 3and 3a, and 4and 4ashowthe characteristic bands of Eu3+, Tb3+, andDy3+, respectively. Magnetic properties were investigatedon 2–4and 2a–4a. The out-of-phase signals (χM″)of 4exhibit a strong frequency dependence, suggestingthe existence of slow magnetic relaxation behavior in 4. [ABSTRACT FROM AUTHOR]