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Both ferroelectric and switchable dielectric behaviors are of great academic value and practical significance, but they usually exist alone. If combine the two properties into one compound, it will be more valuable in practical application. In this paper, quasi-spherical (2-bromoethyl) trimethylammonium cation was used to match with [CdBr4 ]2- anion, and a new organic-inorganic hybrid compound ([BrCH2 CH2 N(CH3 )3 ]+2 [CdBr4 ]2- , BETABCdBr) was obtained and carefully characterized. The results indicate that this compound undergoes two continuous reversible phase transition around 342 K and 390 K. It could respectively exhibit ferroelectric and switchable dielectric properties over different temperature range. This work may provide a new clue to explore new types of bifunctional phase transition smart materials to meet various application requirements.

The organically-templated uranyl selenite, (H2en)[(UO2)(SeO3)(HSeO3)](NO3)·0.5H2O (1) (en = 1,2-ethylenediamine) was synthesized and characterized by elemental analyses, IR spectroscopy, TG, and single-crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic system, space group Pbca, with a = 13.170(3) A, b = 11.055(2) A, c = 18.009(4) A, V = 2621.8(9) A3, M = 1316.19, Z = 4, Dcal = 3.334 g·cm–3, μ(Mo-Kα) = 17.998 mm–1, GOF = 1.059, R1 = 0.0263, wR2 = 0.0532 [I>2σ(I)]. The X-ray diffraction analysis reveals that compound 1 has a three-dimensional (3D) supramolecular structure. It contains negatively charged [UO2(HSeO3)(SeO3)]– inorganic anion layers and is balanced by [H2en]2+ cations and NO3– anions located in the interlayers. Furthermore, the photoluminescence properties of 1 were investigated.

A dysprosium-zinc porphyrin, [DyZn(TPPS)H3O]n (1) (TPPS = tetra(4-sulfonatophenyl)porphyrin), was prepared through solvothermal reactions and structurally characterized by single-crystal X-ray diffraction analyses. Complex 1 features a three-dimensional (3-D) porous open framework that is thermally stable up to 400 °C. Complex 1 displays a void space of 215 A3, occupying 9.2% of the unit cell volume. The fluorescence spectra reveal that it shows an emission band in the red region. The fluorescence lifetime is 39 µsec and the quantum yield is 1.7%. The cyclic voltammetry (CV) measurement revealed one quasi-reversible wave with E1/2 = 0.30 V. Copyright © 2015 John Wiley & Sons, Ltd.

A new type of ionic ferroelectric based on a chiral salen-type Schiff base erbium(III) complex (ErL) was synthesized by the reaction of erbium nitrate with the ligand N,N′-bis(3,5-dichlorosalicylidene)-(1S,2S)-1,2-cyclohexylenediamine (L). The structures of the ligand L and the complex ErL were determined by single-crystal X-ray diffraction. The results indicated that ErIII not only acts as central metal atom to coordinate with two Schiff base ligands, but also as Lewis acid catalyst to promote the partial decomposition of another salen-type Schiff base ligand. The central ErIII atom adopts an octacoordinate square antiprismatic arrangement with Λ absolute configuration, coordinating with all nitrogen and oxygen atoms of two ligands due to the influence of the strong electron-withdrawing group on the Schiff base ligand. The complex ErL exhibits good SHG and ferroelectric properties. The results provide a simple and effective approach to construct rare earth complexes coordinated with nitrogen and oxygen atoms of salen-type Schiff base ligands with technologically important properties such as SHG activity and ferroelectricity.

The uranyl selenite (H2en) [(UO2)(SeO3)(HSeO3)] (NO3)·0.5H2O is synthesized by slow evaporation of an aqueous mixture of UO2(NO3)2, SeO2, and en (56% yield).

A novel heterometallic metal-isonicotinic acid inorganic-organic hybrid complex [Zn0.5(H2O)]{(Hg2Cl5)- [Er(C6NO2H4)3(H2O)2]}(HgCl2)·0.5CH3OH·0.5H2O (1) has been successfully synthesized via a hydrothermal reaction and structurally characterized by single-crystal X-ray diffraction. Complex 1 crystallizes in the space group C2/c of the monoclinic system with eight formula units in a cell: a=34.165(4) A, b=9.4692(8) A, c=24.575(3) A, β =115.090(5)°, V=7200(1) A3, C18.50H21Cl7ErHg3N3O10Zn0.50, Mr=1495.25, Dc=2.759 g/cm3, T=293(2) K, µ(Mo Kα) =15.954 mm−1, F(000) =5400 and R1/wR2=0.0561/0.0909 for 3157 observed reflections [I>2δ(I)] and 6468 unique reflections. Complex 1 is characteristic of a novel 2D {(Hg2Cl5)[Er(C6NO2H4)3(H2O)2]} layered structure constructed from the [Er(C6NO2H4)3(H2O)2] chains interconnected by the Hg2Cl5− linkers. The 2D {(Hg2Cl5)[Er(C6NO2H4)3(H2O)2]} layers, mercury chloride and the lattice water molecules are held together via hydrogen bonds to form a three-dimensional framework with the methanol molecules and the hydrated zinc ions located in the cavities. The magnetic properties show that complex 1 exhibits antiferromagnetic-like interactions.

Two series of Schiff base dioxomolybdenum (VI) complexes of the general formula [MoO2(L)(MeOH)] (L = D-glucosamine-derived Schiff base) have been synthesised, characterised and their asymmetric catalytic activities evaluated through the epoxidation of styrene. The molybdenum complexes with acetyl-protected D-glucosamine Schiff base ligands exhibited higher enanatioselectivity than those with unprotected sugar ligands. Protecting D-glucosamine by acetyl groups is an effective way to improve asymmetric catalytic epoxidation activities.