Yun-Chun Li

Syntheses, structures, and photoluminescence of three cadmium(II) coordination complexes based on pyridine-2,6-dicarboxylic acid and a derivative

Three Cd(II) coordination complexes based on two different pyridine dicarboxylic acids (pyridine-2,6-dicarboxylic acid (H2PDA) and its derivative 4-hydroxypyridine-2,6-dicarboxylic acid (chelidamic acid, H3CAM)), [Cd2(PDA)2(H2O)3]n (1), {[Cd2(HCAM)2(H2O)4]·3H2O}n (2), and [Cd4(HCAM)4(H2O)8] (3) have been isolated under hydrothermal conditions. Compound 1, with H2PDA and Cd(NO3)2·4H2O, exhibits a 1-D chain structure. Compound 2, obtained by using H3CAM instead of H2PDA, contains a different 1-D chain from that of 1. When using CdCl2·2.5H2O and H3CAM, a discrete tetranuclear Cd4 compound (3) was obtained, and the isolated molecules are expanded to a eight-connected CsCl-like topology with point symbol (424·64) through hydrogen bonding interactions. Furthermore, the photoluminescent properties of 1–3 were investigated. Three Cd(II) coordination complexes (1–3) have been obtained under hydrothermal conditions and characterized. Compounds 1 and 2 exhibit 1-D chain structures and the structures are further connected by hydrogen bonding interactions to form the 3-D packing structures, while compound 3 shows a discrete Cd4 structure, which is expanded to a 3-D framework through hydrogen bonds with the CsCl-like eight-connected topology. Fluorescence properties indicate that 1 and 2 yield good luminescence and have potential applications in optical materials.

Review: Single-molecule magnets based on pyridine alcohol ligands

Abstract Single-molecule magnets (SMMs) have attracted attention due to their potential applications in quantum computation and information storage, and many SMMs have been reported in the past two decades. In this review, we summarize the structures and the magnetic exchange interactions of pyridine alcohol-based SMMs to give a possible relationship between structure and magnetic property, providing information to generate new molecule-based magnetic materials. According to the correlated metal centers, these SMMs are separated into three segments to discuss.

Magnetic Nature of the CrIII-LnIII Interactions in [CrIII 2LnIII 3] Clusters with Slow Magnetic Relaxation

Abstract Two 3d‐4f hetero‐metal pentanuclear complexes with the formula {[CrIII 2LnIII 3L10(OH)6(H2O)2]Et3NH} [Ln=Tb (1), Dy (2); HL=pivalic acid, Et3N=triethylamine] have been produced. The metal core of each cluster is made up of a trigonal bipyramid with three LnIII ions (plane) and two CrIII ions (above and below) held together by six μ 3‐OH bridges. Also reported with this series is the diamagnetic CrIII–YIII analogue (3). Fortunately, we successfully prepared AlIII–LnIII analogues with the formula {[AlIII 2LnIII 3L10(OH)6(H2O)2]Et3NH⋅H2O} [Ln=Tb (4), Dy (5)], containing diamagnetic AlIII ions, which can be used to evaluate the CrIII–LnIII magnetic nature through a diamagnetic substitution method. Subsequently, static (dc) magnetic susceptibility studies reveal dominant ferromagnetic interactions between CrIII and LnIII ions. Dynamic (ac) magnetic susceptibility studies show frequency‐dependent out‐of‐phase (χ′′) signals for [CrIII 2TbIII 3] (1), [CrIII 2DyIII 3] (2), and [AlIII 2DyIII 3] (5), which are derived from the single‐ion behavior of LnIII ions and/or the CrIII–LnIII ferromagnetic interactions.