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181.
The synthesis and crystal structure of a new coordination polymeric adduct containing mercury iodide
Yunyin Niu Chunliang Han Hongyun Zhang Guang Yang Yu Zhu 《Journal of chemical crystallography》2006,36(10):679-684
A new organic-inorganic hybrid adduct, [HgI2(dps)]
n
(dps=4,4′-dipyridylsulfide), has been synthesized by the reaction of HgI2 with dps in THF at room temperature. The structure characterization was performed by means of IR, elemental analyses and single crystal X-ray analysis. It crystallizes in space group P2(1)/c with a=5.5522(1) ?, b=12.127(2) ?, c=21.508(4) ?, β=91.84(3)°. The structure consists of distorted tetrahedral Hg(II) centers bridged by dps ligands to form one-dimensional linear chains with C–H···I interaction. Comparison of transition metal assemblies with dps showed that the dimensionality and structure of self-assembled supramolecule depend on the coordination preferences of metal ions, the geometry, bulk, and rigidity of ligands, the number and size of anions, and the supramolecular weak interactions.Supplementary material Crystallographic data for the structure reported in this article has been deposited in the Cambridge Crystallographic Data Center, CCDC No. 285579 for compound 1. The information may be obtained free of charge from the Director, CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK (fax: +44-1223-336033; e-mail: deposit@ccdc.cam.ac.uk or http://www.ccdc.cam.ac.uk). 相似文献
182.
Cs2Hg27, the Mercury‐richest Amalgam with Close Relationship to the Bergman Phases By electrolyzing a solution of cesium iodide in N,N‐dimethylformamide at 2 °C on a mercury cathode the amalgam Cs2Hg27 can be synthesized. It crystallizes in an own cubic structure type (space group , a = 16.557(4) Å). The structure can be rationalized by a system of concentrical polyhedral spheres, in close analogy to the Bergman phases. 相似文献
183.
Pb(18‐crown‐6)Cl2 and Hg(18‐crown‐6)I2 are obtained as transparent colourless crystals of needle and hexagonal shape, respectively, by isothermal evaporation of their dichloromethane solutions. Pb(18‐crown‐6)Cl2 crystallizes with the trigonal crystal system [ , no. 148, a = b = 1176.3(2), c = 1191.8(3) pm, V = 1428.2(5) 106·pm3, Z = 3] whereas Hg(18‐crown‐6)I2 crystallizes with the orthorhombic crystal system (Pnma, no. 62, a = 1613.9(2) pm, b = 2822.2(5) pm, c = 841.3(1) pm, V = 3832(1)106·pm3, Z = 8). Both compounds are characterized by linear MX2 (HgI2 or PbCl2) molecular units which are encrypted by the crown ether. In both cases, the divalent metal ion resides in the middle of the crown ether resulting in a hexagonal bipyramidal coordination environment for the metal cations. The molecular symmetry comes close to D3d. Hg(18‐crown‐6)I2 and Pb(18‐crown‐6)Cl2 differ in the way the single MX2@18‐crown‐6 units are packed. Whereas the Hg(18‐crown‐6)I2 molecules are arranged in a (distorted) cubic closest packing, the Pb(18‐crown‐6)Cl2 molecules adopt a hexagonal closest packing. 相似文献
184.
Michael I. Bruce Natasha N. Zaitseva Brian W. Skelton 《Journal of organometallic chemistry》2008,693(17):2887-2897
Several complexes containing Co3 carbonyl clusters end-capping carbon chains of various lengths are described. Pd(0)/Cu(I)-catalysed reactions between {Co3{μ3-C(CC)2Au(PPh3)}(μ-dppm)(CO)7 and I(CC)2SiMe3 or FcCCI gave {Co3{μ3-C(CC)xR}(μ-dppm)(CO)7 [x = 4, R = SiMe33; x = 3, R = Fc 8]; treatment of 3 with NaOMe and AuCl(PPh3) gave 4 [x = 4, R = Au(PPh3)]. Related preparations of Co3{μ3-C(CC)2[Ru(PP)Cp′]}(μ-dppm)n(CO)9−2n [PP = (PPh3)2, Cp’ = Cp, n = 1, 5; PP = dppe, Cp′ = Cp∗, n = 1, 6; 0, 7] are also described. Syntheses of bis-cluster complexes {Co3(μ-dppm)(CO)7}2(μ-Cx) (x = 14, 12; 16, 9; 18, 11; 26, 10) - the latter being the longest cluster-capped Cx chains so far described - and the mercury-bridged compounds Hg{(CC)xC[Co3(μ-dppm)(CO)7]}2 (x = 1, 13; 2, 14) are reported. The molecular structures of 7, 12, 13 and 14, as well as of Co3(μ3-CCCSiMe3)(μ-dppm)(CO)6(PPh3) (15) and Co3{μ3-CC(O)OEt}(μ-dppm)(CO)7 (16), are reported. 相似文献
185.
Povilas Virbickas Gerda Ziziunaite Arunas Ramanavicius Aušra Valiūnienė 《Electroanalysis》2023,35(4):e202200230
In this research a Hg2+ ion biosensor was developed by combining Prussian blue (PB) with glucose oxidase (GOx) – an enzyme that can be inhibited by Hg2+ ions. An application of PB in the design of Hg2+ ion biosensor enabled detecting changes in hydrogen peroxide reduction current at low operational potential of 0.2 vs Ag|AgCl,KClsat. The described Hg2+ ion biosensor exhibited wide linear range from 27 μM to 247 μM of Hg2+ and higher maximal detectable concentration of Hg2+ than other GOx inhibition-based biosensors, making it convenient for the analysis of samples with high concentration of Hg2+ ions. 相似文献
186.
Poobalasingam Abiman Gregory G. Wildgoose Lei Xiao Richard G. Compton 《Electroanalysis》2008,20(14):1607-1609
The detection of palladium using adsorptive stripping voltammetry reported by Wang et al. (J. Wang, K. Varughese Anal. Chim. Acta 1987, 199, 185 [3]) at a hanging mercury drop electrode is extended to a more convenient solid electrode. To this end a random array of 3.5×108 mercury nanodroplets per cm2 (65 nm average diameter) was electrodeposited on a glassy carbon substrate. Adsorptive stripping voltammetry was performed using 2×10?4 M dimethylglyoxime as a chelating agent for the Pd(II) ion, with accumulation at ?0.20 V vs. SCE for 120 s and a linear detection range of 5–150 μM was determined with a limit of detection of 1.6 μM. 相似文献
187.
New, renewable copper (Hg(Cu)FE) and silver (Hg(Ag)FE) based amalgam film electrodes applied for the determination of elemental sulfur using differential pulse cathodic stripping voltammetry are presented. With surface areas adjustable from 1 to 12 mm2, both electrodes are characterized by very good surface reproducibility (≤2%) and long‐term stability (a few thousand measurement cycles). The mechanical refreshing of the amalgam film takes about 1–2 seconds. The effects of various factors such as instrumental parameters and the supporting electrolyte composition were optimized. Interferences from sulfides are easily removed by the addition of acid, and bubbling with argon, for Hg(Ag)FE. In the case of Hg(Cu)FE, sulfides did not interfere. The calibration graph is linear within the studied range from 16 ng L?1 to 4.8 μg L?1 for Hg(Cu)FE, and up to 6.4 μg L?1 for Hg(Ag)FE (tacc=15 s). The correlation coefficients for the two electrodes were at least 0.997. The detection limits for a low concentration of S(0) and tacc=60 s are as low as 14 ng L?1 for Hg(Cu)FE and 4 ng L?1 for Hg(Ag)FE. The proposed method was successfully applied and validated by studying the recovery of S(0) from spiked river water. 相似文献
188.
Seyyed Javad Sabounchei Hassan Nemattalab Sadegh Salehzadeh Sima Khani Mehdi Bayat Hamid Reza Khavasi 《Polyhedron》2008
Reaction of phosphorus ylide Ph3PCHC(O)C6H4Cl (Y1) with HgX2 (X = Cl, Br and I) and ylide (p-tolyl)3PCHC(O)CH3 (Y2) with HgI2 in equimolar ratios using methanol as solvent leads to binuclear products. The bridge-splitting reaction of binuclear complex [(Y1) · HgCl2]2 by DMSO yields a mononuclear complex containing DMSO as ligand. O-coordination of DMSO is revealed by single crystal X-ray analysis in mononuclear complex of [(Y1) · HgCl2 · DMSO]. C-coordination of ylides is confirmed by X-ray structure of binuclear complex [(Y2) · HgI2]2. Characterization of the obtained compounds was also performed by elemental analysis, IR, 1H, 31P, and 13C NMR. Theoretical studies on mercury(II) complexes of Y1 show that formation of mononuclear complexes in DMSO solution in which DMSO acts as a ligand, energetically is more favorable than that of binuclear complexes. 相似文献
189.
The aim of this work was the synthesis and characterization of new modified sol-gel carbon composite electrodes and their application to the determination of trace mercury species with positive charge. Two types of modified electrodes were synthesized, sol-gel and sol-gel-PVSA carbon composite electrodes. In the last ones, poly(vinylsulfonic acid) (PVSA) was used as a functional polymer entrapped within the sol-gel material due to its cationic exchange properties. In a first stage, parameters affecting both, the sol-gel process and the electrode preparation were optimized. In a second stage, usefulness of developed electrodes applied to the determination of cationic mercury species was evaluated, optimizing the activation, preconcentration, measurement and regeneration steps. Developed electrodes showed very favourable electroanalytical properties for their use as amperometric sensors, such as small size, low cost, simple fabrication and handling, renewability and reusability. By means of an easy and low-cost methodology, satisfactory experimental results were obtained in Hg2+ determination. In this sense, developed analytical methodology showed adequate response times, linear concentration range up to three orders of magnitude (from 5.0 × 10−8 to 5.0 × 10−5 M) and detection limits of 1.5 × 10−8 M (3.0 μg L−1). These results suggest that the incorporation of different receptor molecules at the sol-gel carbon composite material in combination with a selected electrochemical reaction could improve the detection limit achieved and obtain electrochemical sensors adapted to the determination of different species of mercury and other heavy metals. 相似文献
190.
《Arabian Journal of Chemistry》2023,16(2):104501
This study investigates the simultaneous removal of low concentrations of arsenic and mercury ions from synthetic produced water via hollow fiber supported liquid membrane (HFSLM). Results show that HFSLM can remove both arsenic and mercury ions from synthetic produced water to less than 0.02 and 0.001 mg·L-1, respectively. These final concentrations comply with the wastewater standard of Thailand. Percentages of extraction for arsenic and mercury ions proved to be about 100 %. Those of recovery for arsenic and mercury ions reached 70 % and 75 %, respectively. A quantum model based on density functional theory (DFT) is introduced to analyze the forming and breaking of supramolecular complex species in the processes of extraction and recovery, respectively. Furthermore, the concept of Generating Function is applied to construct a mathematical model for forecasting the potential of removing metal ions via HFSLM. The mathematical model conforms to the experimental data, having an average relative deviation of 5 %. The results of this study provide a better understanding of the transport mechanisms of arsenic and mercury ions. 相似文献