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Abstract: Increasing both the energy barrier for magnetization reversal and the coercive field of the hysteresis loop are significant challenges in the field of single‐molecule magnets (SMMs). Coordination geometries of lanthanide ions and magnetic interactions between lanthanide ions are both important for guiding the magnetic behavior of SMMs. We report a high energy barrier of 657 K (457 cm−1) in a diamagnetic‐ion‐diluted lanthanide chain compound with a constrained bisphenoid symmetry (D2d); this energy barrier is substantially higher than the barrier of 567 K (394 cm−1) of the non‐diluted chain compound with intrachain ferromagnetic interactions. Although intrachain magnetic interaction lowers the energy barrier for magnetization reversal, it can greatly enhance the coercive fields and zero‐field remanence of the hysteresis loops, which is crucial for the rational design of high‐performance SMMs. Factors related to the coordination sphere of the lanthanide center, which govern the high magnetic relaxation barriers through the second excited Kramer's doublets and the magnetic interactions that affect the hysteresis loops, were revealed through ab initio calculations. [ABSTRACT FROM AUTHOR]

Luminescent 3D lanthanide metal-organic framework (Ln-MOF) {[Tb2(TATAB)2] ⋅4 H2O ⋅6 DMF} n ( 1) was synthesized under solvothermal conditions by using flexible ligand 4,4′,4′′- s-triazine-1,3,5-triyltri- p-aminobenzoate (TATAB). A phase transition was observed between low temperature and room temperature. The luminescence of 1 could be enhanced by formaldehyde and quenched efficiently by trace amounts of benzaldehyde in solvents such as benzyl alcohol (0.01-2.0 vol %) and ethanol (0.01-2.5 vol %). This is the first use of a Ln-MOF as chemical sensor for both formaldehyde and benzaldehyde. The high sensitivity and selectivity of the luminescence response of 1 to benzaldehyde allows it to be used as an excellent sensor for identifying benzaldehyde and provides a simple and convenient method for detecting traces of benzaldehyde in benzyl alcohol based injections. This work establishes a new strategy for detection of benzaldehyde in benzyl alcohol by luminescent MOFs. [ABSTRACT FROM AUTHOR]

A rare, robust microporous lanthanide metal-organic framework with 1D honeycomb-type channels is presented. Excellent adsorption capabilities for N2, H2, and CO2 and significant selective sorption of CO2 over N2 and CH4 were observed. Moreover, the guest-dependent luminescent behavior of these lanthanide materials shows a potential use for the sensing of small-molecule pollutants such as benzene and acetone. [ABSTRACT FROM AUTHOR]

The combination of the anisotropic DyIII ion and organic radicals as spin carriers results in discrete and one-dimensional lanthanide-radical magnetic materials, namely, [Dy(hfac)3(NITThienPh)2] ( 1) and [Dy2(hfac)6(NITThienPh)2] n ( 2; hfac=hexafluoroacetylacetonate, NITThienPh=2-(5-phenyl-2-thienyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide). Linking monomeric 1 with the DyIII ion leads to the formation of polymeric 2, and the transformation between them is chemically controllable and reversible. The characterization of both static and dynamic magnetic properties shows that the dominant intrachain exchange interaction is important to observe magnetic bistability in 2 rather than that in 1. Monomeric 1 exhibits paramagnetic behavior, whereas polymeric 2 shows the unusual coexistence of superparamagnetic and two-step field-induced metamagnetic behaviors. The antiferromagnetic ground state of 2 does not prevent the dynamic relaxation of the magnetization with the finite-sized effect in the lanthanide-radical system. Energy barriers to thermally activated relaxation for 2 are 53 and 98 K in the low- and high-temperature regimes, respectively. A hysteresis loop is observed with the coercive field of 99 Oe at 2 K. [ABSTRACT FROM AUTHOR]