Anion Effects on Lanthanide(III) Tetrazole-1-acetate Dinuclear Complexes Showing Slow Magnetic Relaxation and Photofluorescent Emission.

Three types of lanthanide complexes based on the tetrazole-1-acetic acid ligand and the 2,2'-bipyridine coligand were prepared and characterized by single-crystal X-ray diffraction, IR spectroscopy, and elemental analyses; the formulas of these complexes are [Ln2(1-tza)4(NO3)2(2,2'-bipy)2] (Ln = Sm (1), Eu (2), Gd (3), Tb (4), Dy (5)), [Dy2(1-tza)4Cl2(2,2'-bipy)2] (6), and [Yb2(1-tza)4(NO3)2(2,2'-bipy)2] (7) (1-tza = tetrazole-1-acetate and 2,2'-bipy = 2,2'-bipyridine). They are dinuclear complexes possessing similar structures but different lanthanide(III) ion coordination geometries because of the distinction of peripheral anions (such as NO3(-) and Cl(-)) and the effect of lanthanide contraction. The variable-temperature magnetic susceptibilities of 1-6 were measured. Both Dy(III) complexes (5 and 6) display field-induced single-molecule magnet behaviors. Ab initio calculations revealed that the Dy(III) complex 6 possesses a more anisotropic Dy(III) ion in comparison to that in 5. The room-temperature photoluminescence spectra of Sm(III) (1), Eu(III) (2), Tb(III) (4), and Dy(III) (5 and 6) complexes exhibit strong characteristic emissions in the visible region, whereas the Yb(III) (7) complex shows near-infrared (NIR) luminescence.

Plastic Crystals with Polar Halochromate Anion: Thermosensitive Dielectrics Based upon Plastic Transition and Dipole Rotation.

Plastic crystals functioning with rotatable components offer new opportunities in areas such as modern optoelectronic materials. Here, by taking advantage of controllable rotation of the polar component within the ion-pair plastic-crystal system, we present two such crystals, namely, (Et4N)(CrO3X) (X = Cl or Br), which are unusual examples exhibiting two-staged thermosensitive dielectric responses above room temperature. The frequency-dependent response in the first stage is due to the structural phase transitions, whereas that in the second stage is induced by dynamic rotation of the polar halochromate anions in their NaCl-type plastic-crystal phases. The intrinsic mechanisms were also explicated by molecular dynamics simulations, providing a direct insight into the dynamic characteristics of these two compounds. These studies show that ionic plastic crystals functioning with polar groups are an attractive candidate as sensitive thermoresponsive dielectric materials.

3-Pyridylacetic-Based Lanthanide Complexes Exhibiting Magnetic Entropy Changes, Single-Molecule Magnet, and Fluorescence.

Four complexes from lanthanides, 3-pyridylacetate, and 1,10-phenanthroline, formulated as [Ln2(3-PAA)2(µ-Cl)2(phen)4](ClO4)2 [Ln = Gd(1), Dy(2), Eu(3), Tb(4), 3-PAA = 3-pyridylacetic acid, phen = 1,10-phenanthroline], were obtained. The four compounds were characterized by IR spectra, thermogravimetric analyses, powder X-ray diffraction, and single-crystal X-ray diffraction. Compounds 1-4 are isomorphous, and they have a dinuclear structure. Magnetic studies reveal that 1 shows the magnetocaloric effect with -ΔS m max = 19.03 J kg-1 K-1 at 2 K for ΔH = 5 T, and 2 displays a field-induced single-molecule magnet with U eff = 19.02 K. The photoluminescent spectra of 3 and 4 exhibit strong characteristic emission, which demonstrate that the ligand-to-EuIII/TbIII energy transfer is efficient.

Poly[aqua-(µ(11)-4,6-dihy-droxy-benzene-1,3-disulfonato)-dipotassium].

In the title salt, [K(2)(C(6)H(4)O(8)S(2))(H(2)O)](n), both K(+) ions exhibit a seven-coordination with K-O bond lengths in the range 2.6600 (14) to 3.0522 (16) Å. One K(+) ion is coordinated by seven O atoms from the sulfonate and phenolic hy-droxy groups of six 4,6-dihy-droxy-benzene-1,3-disulfonate (L(2-)) anions while the other K(+) ion is coordinated by six O atoms from the sulfonate and phenolic hy-droxy groups of five L(2-) anions and one water O atom. The L(2-) anion exhibits chelating-bridging multidentate coordination to potassium, resulting in the formation of a cross-linked three-dimensional network.

Poly[(µ(2)-4,4'-bipyridine)(µ(2)-3,5-dicarboxybenzenesulfonato)silver(I)].

In the title compound, [Ag(C(8)H(5)O(7)S)(C(10)H(8)N(2))](n), the Ag atom is tetra-coordinated by two 4,4'-bipydidine (4,4'-bipy) N atoms and two monodentate sulfonate O atoms of the 5-sulfoisophthalic acid (H(3)sip) ligands. Adjacent Ag atoms are bonded through four sulfonate O atoms, forming a dinuclear unit with an Ag⋯Ag separation of 3.384 (5) Å; they are further linked together by the 4,4'-bipy lignds into a chain. Classical inter-molecular O-H⋯O and non-classical intra-molecular C-H⋯O hydrogen bonds are also observed in the two-dimensional supra-molecuar structure.

Penta-aqua-(acetonitrile-κN)zinc(II) 4,6-dihydroxy-benzene-1,3-disulfonate trihydrate.

In the title compound, [Zn(CH(3)CN)(H(2)O)(5)](C(6)H(4)O(8)S(2))·3H(2)O, the Zn(II) ion lies on a mirror plane and is octa-hedrally coordinated by one acetonitrile ligand and five water mol-ecules. The 4,6-dihydroxy-benzene-1,3-disulfonate anion, acting as a counter-ion, is also located on the mirror plane. The crystal packing is stabilized by O-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular network.

Octanuclear aluminum(III) and iron(III) phosphonate cages encapsulating two Na(I) ions.

Hydrothermal reactions of aluminum(III) nitrate or iron(III) nitrate with N,N-dimethylaminomethane-1,1-diphosphonic acid (H(4)L) and sodium hydroxide lead to two novel isostructural octanuclear metal phosphonate cages encapsulating two Na(I) ions, namely, [Al(8)Na(2)(HL)(2)(H(2)L)(10)(H(2)O)(6)] x 20 H(2)O (1) and [Fe(8)Na(2)(HL)(2)(H(2)L)(10)(H(2)O)(6)] x 22 H(2)O (2). The molecular structure of 1 can be viewed as a three-in-one cluster, in which a central zeolite D6R SBU lookalike aluminophosphonate cage is capped by two symmetry-related aluminophosphonate tetrahedral cages above and below and such a tetrahedral cage, being composed of four zeolite S6R SBU lookalike aluminophosphonate rings, further hexadentately traps one Na(+) ion in its cavity.

Genistein-3'-sulfonic acid dihydrate.

IN THE TITLE COMPOUND [SYSTEMATIC NAME: 5-(5,7-dihydr-oxy-4-oxo-4H-chromen-yl)-2-hydroxy-benzene-sulfonic acid dihydrate], C(15)H(10)O(8)S·2H(2)O, the benzopyran-one ring is not coplanar with the phenyl ring, the dihedral angle between them being 41.35 (3)°. No H atom was placed on the sulphonic acid group because it was not possible to distinguish between the two S=O bonds and the S-O bond. In the crystal, the mol-ecules are linked by classical O-H⋯O and C-H⋯O intra- and inter-molecular hydrogen bonds and aromatic π-π stacking inter-actions [centroid-centroid distance of 3.4523 (14) Šbetween the 1, 4-pyran-one rings and the benzene rings, and 3.6337 (14) Šbetween the benzene rings] into a supra-molecular structure.

Hydrogen-bonded layers directed by the [3-O3S-C6H4-PO3H]2- dianion: catena-poly[[silver(I)-mu-4,4'-bipyridine-kappa2N:N'] 3-[hydroxy(oxido)phosphinoyl]benzenesulfonate trihydrate] and catena-poly[[[tetraaquacobalt(II)]-mu-4,4'-bipyridine-kappa2N:N'] 3-[hydroxy(oxido)phosphinoyl]benzenesulfonate].

Both title compounds, {[Ag(2)(C(10)H(8)N(2))(2)](C(6)H(5)O(6)PS).3H(2)O}(n), (I), and {[Co(C(10)H(8)N(2))(2)(H(2)O)(4)](C(6)H(5)O(6)PS)}(n), (II), respectively, contain similar novel symmetric dimeric [O(3)S-C(6)H(4)-PO(3)H](2-) anions formed via two shared (O...H...O) H atoms on twofold positions between two -PO(3)H(-) groups. The two-coordinate Ag(I) structure features one-dimensional polymeric chains of {[Ag(4,4'-bipy)](2)(2+)}(n) (4,4'-bipy is 4,4'-bipyridine), weakly linked by pi-pi interactions, separated by the anionic dimers which are stabilized into layers by hydrogen bonding to three water molecules. In (II), a twofold crystallographic axis runs through the one-dimensional {[Co(4,4'-bipy)(H(2)O)(4)](2+)}(n) chains containing six-coordinate Co(II); three-dimensional packing is provided by hydrogen bonding using all sulfonate and -PO(3)H(-) O atoms as acceptors and the Co-bound water H atoms as donors. In this latter case, the benzenesulfonate aromatic rings are also constrained to a mirror plane. This report illustrates how a previously unreported dianion can affect the crystallization of polymeric metal complex cations.

trans-N,N,N',N'-Tetra-kis(carboxy-meth-yl)cyclo-hexane-1,2-diammonium tetra-chloridocadmium(II) tetra-hydrate.

In the title compound, (C(14)H(24)N(2)O(8))[CdCl(4)]·4H(2)O, the Cd atom in the tetra-hedral [CdCl(4)](2-) anion lies on a twofold rotation axis, and the diprotonated organic mol-ecule, trans-N,N,N',N'-tetra-kis(carb-oxy-meth-yl)cyclo-hexane-1,2-diammon-ium, has 2 symmetry with the twofold rotation axis running through the mid-point of two C-C bonds in the cyclo-hexane unit. In the crystal structure, classical intra-molecular O-H⋯O and N-H⋯O and inter-molecular O-H⋯O, N-H⋯O, O-H⋯Cl and C-H⋯Cl hydrogen bonds are observed.

Ultrasonic effect on RuO2 nanostructures prepared by direct calcination of two new Ru(II)-organic supramolecular polymers.

Two novel Ru(II) complexes [(η6-p-cymene)RuCl(L1)]PF6 (R1) and [(η6-C6H6)RuCl(L1)]PF6 (R3) with ligand (E)-4-(methylthio)-N-((quinolin-2-yl)methylene)benzenamine (L1), were synthesized and investigated using elemental analysis, IR, 1H NMR, 13C NMR spectroscopy and X-ray crystallography. Complexes R1 and R3 have coordination environments with formulated (η6-p-cymene)Ru(N2Cl) and (η6-C6H6)Ru(N2Cl) respectively. The thermal stabilities of compounds R1 and R3 were studied by thermal gravimetric (TG) and differential scanning calorimetry (DSC). The binding of the complexes R1 and R3 to calf thymus DNA (CT DNA) was investigated by using electronic absorption spectra, fluorescence and redox behavior studies. Such experimental data showed that there are interactions between complexes and CT-DNA and the nature of this binding is electrostatic interaction type. Calcination of ultrasonic treated R1 and R3 results in the formation of nanoparticles of RuO2. The nanoparticles were characterized by IR spectroscopy and X-ray diffraction (XRD). Also size and morphology of nanoparticles were investigated by scanning electron microscopy (SEM).

Two bilayer metal-organic frameworks with rare trinuclear heterometal clusters and tunable photoluminescence.

Two bilayer metal-organic frameworks (MOFs) respectively containing trinuclear Pb/K and Cd/Na clusters have been solvothermally synthesized. Photoluminescence studies showed that they exhibit tunable purple-to-red-to-green and purple-to-green luminescence behaviours by variation of excitation light, respectively.

Novel second-harmonic-generation-active lead(II) phosphinate based on 2-carboxyethyl(phenyl)phosphinate ligand.

The hydrothermal reaction of PbCl(2) with the achiral 2-carboxyethyl(phenyl)phosphinate ligand (H(2)L) afforded a novel lead(II) phosphinate that contains two enantiomers as a racemic mixture, namely, [Pb(HL)(2)] (Λ- and Δ-1). Each enantiomer features a two-fold symmetrical chiral chain, in which the adjacent Pb(2+) ions are doubly bridged by pairs of HL(-) ligands. The uni-oriented stacking of such 1D chains by edge-to-face π···π interactions results in its crystallization in the chiral C2 space group. Complex 1 shows a second harmonic generation response that is ∼2 times that of KDP (KH(2)PO(4)).