Manganese-based layered coordination polymer ([Mn(tfbdc)(4,4'-bpy)(H2O)2], Mn-LCP) with microporous structure was synthesized by reaction of 2,3,5,6-tetrafluoroterephthalatic acid(H2tfbdc) and 4,4'-bipyridine(4,4'-bpy) with manganese(II) acetate tetrahydrate in water solution. Mn-LCP was characterized by elemental analysis, IR spectra, thermogravimetric analysis, X-ray single-crystal structure analysis, and powder X-ray diffraction. Magnetic susceptibility data from 300 to 1.8K show that there is a weak antiferromagnetic exchange between Mn(II) ions in Mn-LCP. As anode material, the Mn-LCP electrode exhibits an irreversible high capacity in the first discharge process and a reversible lithium storage capacity of up to about 390 mA h/g from the fourth cycle. It might provide a new method for finding new electrode materials in lithium-ion batteries.

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The solid–liquid equilibrium of the quaternary system Na+,K+//HPO4 2–,Cl––H2O and its subsystems Na+//HPO4 2–,Cl––H2O, Na+, K+//HPO4 2–,Cl––H2O, Na+,K+//HPO4 2––H2O at 298.2K were investigated by the isothermal solution saturation method. The solubility of salts and the equilibrium solid phases were determined. The ternary phase diagram, quaternary dry-salt phase diagram, and the water-content diagram were constructed. There is one invariant point, two univariant curves, and four crystallization regions in the ternary system Na+//HPO4 2–,Cl– −H2O and K+//HPO4 2–,Cl––H2O. The ternary system Na+,K+//HPO4 2––H2O contains two invariant points, three univariant curves, and six crystallization regions. The quaternary system Na+,K+//HPO4 2–,Cl––H2O contains three invariant points, seven univariant curves, and five crystallization regions corresponding to KCl, NaCl, Na2HPO4·12H2O, Na2HPO4·7H2O, and K2HPO4·3H2O. In the quaternary system, KCl occupies the largest crystallization region while K2HPO4·3H2O crystallization region is the smallest. Three kinds of hydrated salts were found in the system while there is no double salts or solid solution. HPO4 2– is the main factor that affects the relative water content in the liquid phase. All the data and results obtained in this paper are of great significance to the crystallization technology of K2HPO4 and the new production process of KH2PO4.

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Two new metal complexes, {[Cd2(μ2‐H2pdc)2(H2O)8]·[Cd2(H2pdc)4(H2O)2(μ2‐Cl)2]}·2H2O (1), and [Ba2(H2pdc)4(H2O)8]·2H2O (2) (H3pdc = 3, 4‐pyrazoledicarboxylic acid), were synthesized and characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. The crystal structures show that compound 1 is an independent unit consisting of two discrete dinuclear complex ions [Cd2(μ2‐H2pdc)2(H2O)8]2+ cation and [Cd2(H2pdc)4(H2O)2(μ2‐Cl)2]2– anion, and the two kinds of ions are linked by hydrogen bonds and electrostatic interactions to generate a 3D supramolecular network. Complex 2 is a common dinuclear structure, which is further assembled to a 3D supramolecular network through intermolecular hydrogen bonds and π–π stacks. The hydrogen bonding interactions involving lattice water or coordinated water molecules all exist in complexes 1 and 2. Notably, three coordination modes of 3, 4‐pyrazoledicarboxylic acid were observed. The thermal and photoluminescent properties of complexes 1 and 2 in the solid state were also investigated.