scholarly journals Coordination polymers of Fe(III) with ligands derived from dinaphthyl-, dinaphthylthio- and dinaphthyldithiophosphinic acids

2002 ◽  
Vol 67 (8-9) ◽  
pp. 617-624 ◽  
Author(s):  
Ioan Rosca ◽  
Daniel Sutiman ◽  
Mihaela Vizitiu ◽  
Doina Sibiescu ◽  
Adrian Cailean ◽  
...  

The synthesis and the study of some coordination polymers derived from the interaction of the acetylacetonate of Fe(III) with dinaphthylphosphinic acid, dinaphthylthiophosphinic acid and dinaphthyldithiophosphinic acid are presented. The methods applied for the study were chemical analysis, gel chromatography, M?ssbauer and IR absorption spectroscopy, X-ray diffraction and thermogravimetric analysis from which the kinedic parameters of the thermal decomposition reactions were determined. The semiconductive properties of the synthesized compounds were also examined. Based on the obtained experimental data and on literature indications, the structural formulae of these compounds were assigned.

Crystals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 664 ◽  
Author(s):  
Chang-Jie Liu ◽  
Tong-Tong Zhang ◽  
Wei-Dong Li ◽  
Yuan-Yuan Wang ◽  
Shui-Sheng Chen

Two Zn(II) coordination polymers (CPs) [Zn(L)(pphda)] (1) and [Zn(L)(ophda)]·H2O (2) were prepared by reactions of ZnSO4·7H2O based on the N-donor 1,4-di(1H-imidazol-4-yl)benzene (L) ligand and two flexible carboxylic acids isomers of 1,4-phenylenediacetic acid (H2pphda) and 1,2-phenylenediacetic acid (H2ophda) as mixed ligands, respectively. Structures of CPs 1 and 2 were characterized by elemental analysis, Infrared spectroscopy (IR), thermogravimetric analysis and single-crystal X-ray diffraction. The CP 1 is a fourfold interpenetrating 66-diamond (dia) architecture, while 2 is a 2D (4, 4) square lattice (sql) layer based on the Zn2(cis-1,2-ophda2−)2 binuclear Zn(II) subunits. The luminescent property, including luminescence lifetime and quantum yield (QY), have been investigated for CPs 1 and 2.


Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4431 ◽  
Author(s):  
Lingshu Meng ◽  
Lun Zhao ◽  
Guanlin Guo ◽  
Xin Liu ◽  
Zhijun Liang ◽  
...  

In this study, three new 3D coordination polymers (CPs), {[Cd3(L)(H2O)6]·H2O}n (1), {[Cu1.5(L)0.5(bimb)1.5]·5H2O·DMF}n (2), and {[Mn1.5(H3L)(bibp)0.5(H2O)2]·3H2O}n (3) (bimb= 1,3-bis(imidazol-1-yl)benzene, bibp= 1,4-bis((4-imidazol-1-yl)benzyl)piperazine), were prepared under solvothermal or hydrothermal conditions based on a hexadentate ligand (1,3,5-triazine-2,4,6-triamine hexa-acetic acid (H6L)). Structural elucidations were carried out by IR spectra along with single-crystal X-ray diffraction analysis, while thermogravimetric analysis (TGA) (dynamic and isothermal) and XRD techniques were used for property evaluations of the polymers. Furthermore, the fluorescence properties and detection of the Fe3+ ions in 1 were tested at room temperature, and the electrochemical behavior of 2 is also stated in this article.


Author(s):  
Svetlana Cherepanova ◽  
Dina Markovskaya ◽  
Ekaterina Kozlova

The X-ray diffraction (XRD) pattern of a deleterious phase in the photocatalyst based on Cd1 − xZnxS/Zn(OH)2contains two relatively intense asymmetric peaks withd-spacings of 2.72 and 1.56 Å. Very small diffraction peaks with interplanar distances of (d) ≃ 8.01, 5.40, 4.09, 3.15, 2.49 and 1.35 Å are characteristic of this phase but not always observed. To identify this phase, the XRD patterns for sheet-like hydroxide β-Zn(OH)2and sheet-like hydrozincite Zn5(CO3)2(OH)6as well as for turbostratic hydrozincite were simulated. It is shown that the XRD pattern calculated on the basis of the last model gives the best correspondence with experimental data. Distances between layers in the turbostratically disordered hydrozincite fluctuate aroundd≃ 8.01 Å. This average layer-to-layer distance is significantly higher than the interlayer distance 6.77 Å in the ordered Zn5(CO3)2(OH)6probably due to a deficiency of CO32−anions, excess OH−and the presence of water molecules in the interlayers. It is shown by variable-temperature XRD and thermogravimetric analysis (TGA) that the nanocrystalline turbostratic nonstoichiometric hydrozincite-like phase is quite thermostable. It decomposes into ZnO in air above 473 K.


Minerals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 34
Author(s):  
Iván A. Reyes ◽  
Mizraim Flores ◽  
Elia G. Palacios ◽  
Hernán Islas ◽  
Julio C. Juárez ◽  
...  

Manganese is a widely used element in the steel industry; its main source is a mineral named rhodochrosite (MnCO3). For industrial usage, rhodochrosite is reduced to different manganese oxides by means of nodulation furnaces. In this study, rhodochrosite was thermally analyzed at temperatures ranging from 100 °C to 1200 °C. XRD (Powder X-ray diffraction), XRF (X-ray fluorescence), AAS (Atomic Absorption Spectrometry), and FESEM-EDX (Field Emission Scanning Electron Microscopy-Energy Dispersive X-Ray Spectrometry) were used to characterize the mineral and the residues were analyzed by XRD and FTIR (Fourier-transform infrared spectroscopy) to determine the stoichiometry of the thermal decomposition reactions. Three mass losses were observed, the first attributed to the transformation from carbonate to manganese (III) oxide, the second to the reduction to manganese tetroxide, and the third to the decomposition of calcium carbonate (CaCO3) present as a contaminant in the studied mineral. Thermal decomposition kinetics shows that the first mass loss required 17.91 kJ mol−1, indicating a control by mass transport-controlled process. For the second and third mass loss, the apparent activation energy of 112.41 kJ mol−1 and 64.69 kJ mol−1 was obtained respectively, indicating that both mass loss events were rate-controlled.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Long Tang ◽  
HuanHuan Wang ◽  
YuHao Fu ◽  
XiangYang Hou ◽  
Xiao Wang ◽  
...  

AbstractTwo new coordination polymers (CPs), [Zn(npba)2] (1) and [Cd(npba)2] (2), have been hydrothermally synthesized from Zn(NO3)2·6H2O/Cd(NO3)2·6H2O and 3-nitro-5-(pyridin-3-yl) benzoic acid (Hnpba). The products have been characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, and single-crystal X-ray diffraction. In CP 1, the four-coordinated Zn(II) centers are bridged by npba ligands to generate chains, which are connected through arene π–π stacking interactions to generate a layer structure. In CP 2, the six-coordinated Cd(II) centers are also bridged by npba ligands to form chains with similar connectivity. The photoluminescence properties of CPs 1 and 2 were studied.


2016 ◽  
Vol 69 (11) ◽  
pp. 1261 ◽  
Author(s):  
Masoumeh Tabatabaee ◽  
Boris-Marko Kukovec ◽  
Saeed Amjad ◽  
Masoud R. Shishebor

Two novel barium(ii) 2D coordination polymers, {[Ba(µ-H2O)(H2O)2(µ-pyzdc)]}n (1) and {[Ba(H2O)2(µ-Hpyzdc)(Hpyzdc)]⋅2H2O}n (2) (pyzdcH2 = pyrazine-2,3-dicarboxylic acid), were prepared by reaction of barium(ii) chloride dihydrate and pyrazine-2,3-dicarboxylic acid under similar experimental conditions (slightly different pH values) and characterised by elemental analysis, IR spectroscopy, and thermogravimetric analysis/differential thermal analysis methods. Their crystal structures were determined by single-crystal X-ray structure analysis and it was revealed that the barium(ii) ion has a distorted bicapped square antiprismatic coordination geometry in 1 and a distorted tricapped trigonal prismatic geometry in 2, composed of water molecules, carboxylate O, and pyrazine N atoms in both cases. The polymers 1 and 2 have different connectivity, as the pyrazine-2,3-dicarboxylate ion acts as multidentate bridging ligand in both 1 and 2, but also as an N,O′-bidentate terminal ligand in 2. There are terminal coordinated water molecules in both 1 and 2, but bridging water molecules are present only in 1 and water molecules of crystallisation only in 2. BaCO3 nanoparticles were formed by thermal decomposition of 1 in the presence of polyethylene glycol, and their structure and morphology were studied by powder X-ray diffraction and scanning electron microscopy. According to the powder X-ray diffraction pattern, BaCO3 was formed with an orthorhombic witherite structure.


1993 ◽  
Vol 8 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Patricia Bénard ◽  
Jean Paul Auffrédic ◽  
Daniel Louër

The decomposition reactions of two zirconium hydroxide nitrates Zr(OH)2(NO3)2·(4+x)H2O and α-Zr(OH)2 (NO3)2·(1+x)H2O (0≤x≤1) have been studied by thermogravimetric analysis and high-temperature X-ray powder diffractometry (HTXRD), in nitrogen gas environment. The decomposition reaction sequences were clearly displayed by the HTXRD technique. They are different for the two precursors, except the formation of amorphous zirconia at low temperature (200 °C) and crystalline zirconia at about 390 °C. Three modifications of Zr(OH)2(NO3)2·H2O (α,β,γ) were identified. Their X-ray powder diffraction patterns were indexed by the successive dichotomy method. The unit cells are triclinic and present some parametric and volumetric similarities from each other and also with that of their precursor. Moreover, the thermal decomposition sequences of Zr(OH)2(NO3)2·(4+x)H2O and α-Zr(OH)2(NO3)2·(1+x)H2O include the formation of anhydrous oxide nitrate ZrO(NO3)2 and anhydrous hydroxide nitrate Zr(OH)2(NO3)2, respectively.


2009 ◽  
Vol 283-286 ◽  
pp. 539-544 ◽  
Author(s):  
R.I. Gulyaeva ◽  
Evgeny N. Selivanov ◽  
A.N. Mansurova

The chemistry and the kinetics of the reduction of calcium containing CaFeSO and Ca2FeCuSO3) oxysulfides in a mixture of flowing gases that contains (75% CO) carbon monoxide and argon have been investigated by thermogravimetric analysis and X-ray diffraction. Experiments were carried out on the synthesized samples by heating up to 1270 K with heating rates of 5-20 K/min. The Netzsch Thermokinetics program was used for the analysis of the experimental data. Kinetic parameters of reduction processes are determined.


Sign in / Sign up

Export Citation Format

Share Document