Journal articles: 'CuII system'

1

Amendola, Valeria, Massimo Boiocchi, Yuri Diaz Fernandez, Carlo Mangano, and Piersandro Pallavicini. "A Solvent-Dependent and Electrochemically Controlled Self-Assembling/Disassembling System." Collection of Czechoslovak Chemical Communications 68, no. 9 (2003): 1647–62. http://dx.doi.org/10.1135/cccc20031647.

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The bis-bidentate ligand R,S-1,2-diphenyl-N,N'-bis(2-quinolinemethylidene)ethane-1,2-diamine (ligand 4), containing two (iminomethyl)quinoline moieties separated by a cis-1,2-diphenylethylene spacer, forms stable complexes with both CuI and CuII. With CuII, the monomeric 1:1 complex [CuII(4)]2+ is obtained both in CH3CN and CH2Cl2. With CuI and overall 1:1 metal/ligand molar ratio, an equilibrium mixture is obtained in CH3CN, consisting of [CuI(4)2]+, [CuI2(4)2]2+ and [CuI2(4)(CH3CN)4]2+. The preponderant species is the two-metal one-ligand "open" complex [CuI2(4)(CH3CN)4]2+, in which each Cu+ cation is coordinated in a tetrahedral fashion by one (iminomethyl)quinoline unit and by two CH3CN molecules. Precipitation from the equilibrium mixture yields only crystals of [CuI2(4)(CH3CN)4](ClO4)2·2CH3CN, whose crystal and molecular structures have been determined. On the other hand, in the poorly coordinating CH2Cl2 solvent, only the dimeric helical [CuI2(4)2]2+ complex is obtained, when the overall metal/ligand 1:1 molar ratio is chosen. Addition of large quantities of acetonitrile to solutions of [CuI2(4)2]2+ in dichlorometane results in the formation of [CuI2(4)(CH3CN)4]2+, i.e. in the solvent-driven disassembling of the CuI helicate. While electrochemistry in CH3CN is poorly defined due to the presence of more than one CuI species, cyclic voltammetry experiments carried out in CH2Cl2 revealed a well defined behavior, with irreversible oxidation of [CuI2(4)2]2+ and irreversible reduction of [CuII(4)]2+ taking place at separate potentials (∆E ≈ 700 mV). Irreversibility and separation of the redox events are due to the self-assembling and disassembling processes following the reduction and oxidation, respectively.

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2

Rogers, Ciaran, Deepak Asthana, Adam Brookfield, et al. "Modelling Conformational Flexibility in a Spectrally Addressable Molecular Multi-Qubit Model System." Angewandte Chemie Internation Edition 61, no. 45 (2022): e202207947. https://doi.org/10.1002/anie.202207947.

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Dipolar coupled multi-spin systems have the potential to be used as molecular qubits. Herein we report the synthesis of a molecular multi-qubit model system with three individually addressable, weakly interacting, spin 1=2 centres of differing g-values. We use pulsed Electron Paramagnetic Resonance (EPR) techniques to characterise and separately address the individual electron spin qubits; CuII, Cr7Ni ring and a nitroxide, to determine the strength of the inter-qubit dipolar interaction. Orientation selective Relaxation-Induced Dipolar Modulation Enhancement (os-RIDME) detecting across the CuII spectrum revealed a strongly correlated CuII-Cr7Ni ring relationship; detecting on the nitroxide resonance measured both the nitroxide and CuII or nitroxide and Cr7Ni ring correlations, with switchability of the interaction based on differing relaxation dynamics, indicating a handle for implementing EPR-based quantum information processing (QIP) algorithms.

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3

Benari, MD, and GT Hefter. "Electrochemical Characteristics of the Copper(II)-Copper(I) Redox Couple in Dimethyl Sulfoxide Solutions." Australian Journal of Chemistry 43, no. 11 (1990): 1791. http://dx.doi.org/10.1071/ch9901791.

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A study of the electrochemical characteristics of the copper(II)/copper(I) redox couple has been made in chloride and bromide media in dimethyl sulfoxide (Me2SO) and their aqueous analogues. The formal potentials of the CuII/CuI couple in the Me2SO media are approximately 0.15 V less positive than in their aqueous counterparts probably due to a combination of solvation and complexation effects. Diffusion coefficients for both CuI and CuII are 5-10 times lower in Me2SO than in H2O as a result of the higher viscosity of Me2SO solutions. Heterogeneous electron-transfer rate constants for the CuII/CuI system on platinum are also an order of magnitude smaller than in aqueous solution. In general the electrochemical characteristics of the CuII/CuI system parallel those reported elsewhere for the FeIII/FeII couple. However, a detailed investigation of the CuII/CuI system by cyclic voltammetry indicates that the overall electrode process is complex, probably involving a quasi-reversible electron-transfer step coupled to a rate-determining loss of Cl - from CuII.

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4

Bobonazarzoda, Gulruhsor, Jahongul Davlatshoeva, Mubashirhon Rakhimova, Mahmurod Guriev, and Farida Miraminzoda. "Complexation processes of CuII with imidazole." From Chemistry Towards Technology Step-By-Step 6, no. 1 (2025): 81–87. https://doi.org/10.52957/2782-1900-2025-6-1-81-87.

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The purpose of the study is to investigate the complexation process in the heterogeneous Cu(0)-Cu(II)-imidazole-water system by the classical Clark-Nikolsky oxidation potential method at a temperature of 288.15 K and a solution ionic strength of 1.0 mol/L. The authors found the formation of the following coordination compounds in this system: [Cu(HL)2]3+, [CuHL(OH)]2+, [Cu(HL)2(OH)]2+, [Cu2(HL)2(OH)2]4+, [Cu2(HL)2(OH)3]3+. The complexation process proceeds in a rather wide pH range from 1.0 to 10.5.

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5

Chruscinska, Elzbieta, Eugenio Garribba, Giovanni Micera, and Daniele Sanna. "Hydrolytic and Dinuclear Species Formed by Copper(II) with Di-, Tri- and Tetra-peptides Containing Proline in the Second Position." Journal of Chemical Research 23, no. 3 (1999): 240–41. http://dx.doi.org/10.1177/174751989902300335.

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6

Walger, Elsa, Nathalie Marlin, Gérard Mortha, Florian Molton, and Carole Duboc. "Hydroxyl Radical Generation by the H2O2/CuII/Phenanthroline System under Both Neutral and Alkaline Conditions: An EPR/Spin-Trapping Investigation." Applied Sciences 11, no. 2 (2021): 687. http://dx.doi.org/10.3390/app11020687.

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The copper–phenanthroline complex CuI(Phen)2 was the first artificial nuclease studied in biology. The mechanism responsible for this activity involves CuII(Phen)2 and H2O2. Even if H2O2/Cu systems have been extensively studied in biology and oxidative chemistry, most of these studies were carried out at physiological pH only, and little information is available on the generation of radicals by the H2O2/CuII-Phen system. In the context of paper pulp bleaching to improve the bleaching ability of H2O2, this system has been investigated, mostly at alkaline pH, and more recently at near-neutral pH in the case of dyed cellulosic fibers. Hence, this paper aims at studying the production of radicals with the H2O2/CuII-Phen system at near-neutral and alkaline pHs. Using the EPR/spin-trapping method, HO• formation was monitored to understand the mechanisms involved. DMPO was used as a spin-trap to form DMPO–OH in the presence of HO•, and two HO• scavengers were compared to identify the origin of the observed DMPO–OH adduct, as nucleophilic addition of water onto DMPO leads to the same adduct. H2O2 decomposition was enhanced by the addition of CuII–Phen (and only slightly by addition of CuSO4), reaching a level similar to the Fenton reagent at near-neutral pH. This evidences the role of Phen, which improves the effect of CuII by tuning the electronic structure and structural properties of the corresponding CuII complexes.

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7

Dalecki, Alex G., Mehri Haeili, Santosh Shah, et al. "Disulfiram and Copper Ions Kill Mycobacterium tuberculosis in a Synergistic Manner." Antimicrobial Agents and Chemotherapy 59, no. 8 (2015): 4835–44. http://dx.doi.org/10.1128/aac.00692-15.

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ABSTRACTTuberculosis is a severe disease affecting millions worldwide. Unfortunately, treatment strategies are hampered both by the prohibitively long treatment regimen and the rise of drug-resistant strains. Significant effort has been expended in the search for new treatments, but few options have successfully emerged, and new treatment modalities are desperately needed. Recently, there has been growing interest in the synergistic antibacterial effects of copper ions (CuII/I) in combination with certain small molecular compounds, and we have previously reported development of a drug screening strategy to harness the intrinsic bactericidal properties of CuII/I. Here, we describe the copper-dependent antimycobacterial properties of disulfiram, an FDA-approved and well-tolerated sobriety aid. Disulfiram was inhibitory to mycobacteria only in the presence of CuII/Iand exerted its bactericidal activity well below the active concentration of CuII/Ior disulfiram alone. No other physiologically relevant bivalent transition metals (e.g., FeII, NiII, MnII, and CoII) exhibited this effect. We demonstrate that the movement of the disulfiram-copper complex across the cell envelope is porin independent and can inhibit intracellular protein functions. Additionally, the complex is able to synergistically induce intracellular copper stress responses significantly more than CuII/Ialone. Our data suggest that by complexing with disulfiram, CuII/Iis likely allowed unfettered access to vulnerable intracellular components, bypassing the normally sufficient copper homeostatic machinery. Overall, the synergistic antibacterial activity of CuII/Iand disulfiram reveals the susceptibility of the copper homeostasis system ofMycobacterium tuberculosisto chemical attacks and establishes compounds that act in concert with copper as a new class of bacterial inhibitors.

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8

Yogesh, Kumar, Sharda, Garg Ashish, and Pandey Rajayashree. "Polarographic behavior of CuII-theophylline complex." Journal of Indian Chemical Society Vol. 87, Oct 2010 (2010): 1231–34. https://doi.org/10.5281/zenodo.5804927.

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Electrochemical Laboratory, Department of Chemistry, University of Rajasthan, Jaipur-302 055, Rajasthan, India E-mail: yogesh.kmar@yahoo.com Manuscript received 24 December 2009, revised 6 April 2010, accepted 13 April 2010 The CuII-theophylline complex is best formed at pH 4.5. The CuII-theophylline complex formed is in 1 : 1 ratio. The system is irreversible and the kinetic and thermodynamic parameters have been determined.

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9

Cini, Renzo, Rebecca Pogni, Riccardo Basosi, et al. "Oxygen Radical Scavenger Activity, EPR, NMR, Molecular Mechanics and Extended-Hückel Molecular Orbital Investigation of the Bis(Piroxicam)Copper(II) Complex." Metal-Based Drugs 2, no. 1 (1995): 43–56. http://dx.doi.org/10.1155/mbd.1995.43.

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The oxygen radical scavenger activity (ORSA) of [CuII(Pir)2] (HPir = Piroxicam = 4-hydroxy -2- methyl -N-2- pyridyl -2H- 1,2-benzothiazine -3- carboxamide 1,1-dioxide) was determined by chemiluminescence of samples obtained by mixing human neutrophils (from healthy subjects) and [CuII(Pir)2(DMF)2] (DMF = N,N -dimethylformammide) in DMSO/GLY/PBS (2:1:2, v/v) solution (DMSO = dimethylsulfoxide, GLY = 1,2,3-propantriol, PBS = Dulbecco’s buffer salt solution). The ratio of the residual radicals, for the HPir (1.02·10−4M) and [CuII(Pir)2(DMF)2] (1.08·10−5M) /HPir (8.01·10−5M) systems was higher than 12 (not stimulated) [excess of piroxicam was added (Cu/Pir molar ratio ≈1:10) in order to have most of the metal complexed as bischelate]. In contrast, the ratio of residual radicals for the CuCl2 (1.00·10−5M) and [CuII(Pir)2(DMF)2] (1.08·10−5M)/Hpir (8.01·10−5M)system was 5. The [CuII(Pir)2] compound is therefore a stronger radical scavenger than either HPir or CuCl2. A molecular mechanics (MM) analysis of the gas phase structures of neutral HPir, its zwitterionic (HPir+-) and anionic (Pir-) forms, and some CuII-piroxicam complexes based on X-ray structures allowed calculation of force constants. The most stable structure for HPir has a ZZZ conformation similar to that found in the CuII (and CdII complexes) in the solid state as well as in the gas phase. The structure is stabilized by a strong H bond which involves the N(amide)-H and O(enolic) groups. The MM simulation for the [CuII(Pir)2(DMF)2] complex showed that two high repulsive intramolecular contacts exist between a pyridyl hydrogen atom of one Pir- molecule with the O donor of the other ligand. These interactions activate a transition toward a pseudo-tetrahedral geometry, in the case the apical ligands are removed. On refluxing a suspension of [CuII(Pir)2(DMF)2] in acetone a brown microcystalline solid with the Cu(Pir)2·0.5DMF stoichiometry was in fact prepared. C13 spin-lattice relaxation rates of neutral, zwitterionic and anionic piroxicam, in DMSO solution are explained by the thermal equilibrium between the three most stable structures of the three forms, thus confirming the high quality of the force field. The EPR spectrum of [CuII(Pir)2(DMF)2] (DMSO/GLY, 2:1, v/v, 298 and 110 K) agrees with a N2O2+O2 pseudo-octahedral coordination geometry. The EPR spectrum of CuII(Pir)2·0.5DMF agrees with a pseudo-tetrahedral coordination geometry. The parameters extracted from the room temperature spectra of the solution phases are in agreement with the data reported for powder and frozen solutions. The extended-Hückel calculations on minimum energy structures of [CuII(Pir)2(DMF)2] and [CuII(Pir)2] (square planar) revealed that the HOMOs have a relevant character of dx2−y2. On the other hand the HOMO of a computer generated structure for [CuII(Pir)2] (pseudo-tetrahedral) has a relevant character of dxy atomic orbital. A dxy orbital is better suited to allow a dπ-pπ interaction to the O2- anion. Therefore this work shows that the anti-inflammatory activity of piroxicam could be due in part to the formation of [CuII(Pir)2] chelates, which can exert a SOD-like activity.

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10

Marino, Nadia, Francesc Lloret, Miguel Julve, and Giovanni De Munno. "Chemical and Structural Versatility in the Copper/2,2′-Bipyrimidine/Iodide System: A Regular Alternating Mixed-Valent Cu(II)-Cu(I) Chain Showing Unusually Similar Metal Coordination Environments." Magnetochemistry 11, no. 3 (2025): 20. https://doi.org/10.3390/magnetochemistry11030020.

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The reaction in reagent grade acetone of copper(II) nitrate hexahydrate, 2,2′-bipyrimidine (bpm) and potassium iodide in a 1:2:2 molar ratio afforded three different products: an unreduced Cu(II) species, a fully reduced Cu(I) species and a mixed-valent Cu(II)/Cu(I) species. Of these, only the unreduced Cu(II) complex of formula [CuII(bpm)3](I3)(I) (1) could be structurally characterized, the other two products being initially only isolated as amorphous powders. X-ray quality, beautifully shaped, quasi-black prismatic crystals of compound 2, namely {[CuI(I3)CuII(I)(bpm)2](I3)}n, and brick-reddish parallelepipeds of compound 3, namely {[CuI2 (μ-I)2(bpm)]}n, were successively obtained through the slow diffusion in H-shaped tubes of aqueous solutions of the three reagents, after extensive optimization of the crystallization conditions. Compound 1 consists of a rare tris(2,2′-bipyrimidine)copper(II) monomeric dication, charge balanced by both iodide and triiodide anions. Compound 3, whose structure as well as optical and photocatalytic properties were recently disclosed, consists of a regular alternating μ-bpm/di-μ-iodide copper(I) chain. Finally, compound 2 consists of a rare, regular alternating mixed-valent Cu(II)-Cu(I) μ-bpm copper chain, showing unusual similarities in the metal coordination environment. The magnetic properties of compound 2 remarkably reveal a very weak antiferromagnetic coupling between the paramagnetic Cu(II) ions which are well separated both intra- and inter-chain.

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11

Sun, You-Min, Li-Li Wang, Yong-Shan Ma, Cheng-Bu Liu, and Zhao-Jie Cui. "Magnetic exchange behavior of a long-range CuII system through the diamagnetic CuI2 unit bridge: A DFT study." Polyhedron 30, no. 18 (2011): 3224–27. http://dx.doi.org/10.1016/j.poly.2011.04.021.

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12

Xu, Zhian, Liang Xiao, Xuetao Fan, et al. "Spray-Assisted Interfacial Polymerization to Form CuII/I@CMC-PANI Film: An Efficient Dip Catalyst for A3 Reaction." Nanomaterials 12, no. 10 (2022): 1641. http://dx.doi.org/10.3390/nano12101641.

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A novel and interesting method for the preparation of carboxymethylcellulose–polyaniline film-supported copper catalyst (CuII/I@CMC-PANI) has been developed via spray-assisted interfacial polymerization. Using copper sulfate as an initiator, spraying technology was introduced to form a unique interface that is perfectly beneficial to the polymerization of aniline monomers onto carboxymethylcellulose macromolecule chains. To further confirm the composition and structure of the as-prepared hybrid film, it was systematically characterized by inductively coupled plasma (ICP), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and thermogravimetric analysis (TGA) techniques. The Cu content in the fresh CuII/I@CMC-PANI film was determined to be 1.805 mmol/g, and spherical nanoparticles with an average size of ca. 10.04 nm could be observed in the hybrid film. The CuII/I@CMC-PANI hybrid film was exerted as a dip catalyst to catalyze the aldehyde–alkyne–amine (A3) coupling reactions. High yields of the products (up to 97%) were obtained in this catalytic system, and the catalyst could be easily picked up from the reaction mixture by tweezers and reused for at least six consecutive runs, without any discernible losses in its activity in the model reaction. The dip catalyst of CuII/I@CMC-PANI, with easy fabrication, convenient deployment, superior catalytic activity, and great reusability, is expected to be very useful in organic synthesis.

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Ali, Ibraheem O., Hisham S. Nassar, Ahmed M. Naglah, Laila M. Al-Harbi, and Ahmed A. Elhenawy. "Structural and Spectroscopic Characteristics of NiII and CuII Complexes with Poly (Vinyl Alcohol-Nicotinic Acid) Copolymers for Photocatalytic Degradation of Indigo Carmine Dye." Crystals 11, no. 10 (2021): 1244. http://dx.doi.org/10.3390/cryst11101244.

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Poly-vinyl-alcohol (PVA) has been cross-linked chemically with nicotinic-acid (NA) in an aqueous medium. The copolymers were complexed with NiII and CuII ions. The complexes and copolymers were analyzed using FT-IR and UV–Visible spectroscopy, XRD and TGA, but copolymers were extra analyzed with nuclear magnetic resonance (1H NMR). FT-IR spectra of copolymer revealed the presence of C=O & C–N groups due to the esterification of PVA-NA. The Cu/NA-PVA formed via bidentate interaction of the pyridinyl and carboxyl of NA. EPR/UV-vis data shows the square-planar geometry for NiII and CuII complexes. The adsorption of IC dye onto CuII/NA-PVA complex was noticeably greater (90%) in 35 min than NiII/NA-PVA. The DFT\B3LYP with 6- 311G* quantum chemical calculations were carried out for tested compounds. The DFT was conducted to examine an interaction mode of the target compounds with the reaction system. The QSPR was calculated as: optimization geometries, (FMOs), chemical-reactivities and NLO for the copolymers. The (MEPs) were figured to predict the interaction behavior of the ligand and its complexes.

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14

Powell, Kipton J., Paul L. Brown, Robert H. Byrne, et al. "Chemical speciation of environmentally significant metals with inorganic ligands. Part 4: The Cd2+ + OH–, Cl–, CO32–, SO42–, and PO43– systems (IUPAC Technical Report)." Pure and Applied Chemistry 83, no. 5 (2011): 1163–214. http://dx.doi.org/10.1351/pac-rep-10-08-09.

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The numerical modeling of CdII speciation amongst the environmental inorganic ligands Cl–, OH–, CO32–, SO42–, and PO43– requires reliable values for the relevant stability (formation) constants. This paper compiles and provides a critical review of these constants and related thermodynamic data. It recommends values of log10βp,q,r° valid at Im = 0 mol kg–1 and 25 °C (298.15 K), along with the equations and empirical reaction ion interaction coefficients, ∆&epsilon; , required to calculate log10βp,q,r values at higher ionic strengths using the Brønsted–Guggenheim–Scatchard specific ion interaction theory (SIT). Values for the corresponding reaction enthalpies, ∆rH, are reported where available. Unfortunately, with the exception of the CdII-chlorido system and (at low ionic strengths) the CdII-sulfato system, the equilibrium reactions for the title systems are relatively poorly characterized. In weakly acidic fresh water systems (–log10 {[H+]/c°} &lt; 6), in the absence of organic ligands (e.g., humic substances), CdII speciation is dominated by Cd2+(aq), with CdSO4(aq) as a minor species. In this respect, CdII is similar to CuII [2007PBa] and PbII [2009PBa]. However, in weakly alkaline fresh water solutions, 7.5 &lt; –log10 {[H+]/c°} &lt; 8.6, the speciation of CdII is still dominated by Cd2+(aq), whereas for CuII [2007PBa] and PbII [2009PBa] the carbonato- species MCO3(aq) dominates. In weakly acidic saline systems (–log10 {[H+]/cϒ} &lt; 6; –log10 {[Cl–]/c°} &lt; 2.0) the speciation is dominated by CdCln(2–n)+ complexes, (n = 1–3), with Cd2+(aq) as a minor species. This is qualitatively similar to the situation for CuII and PbII. However, in weakly alkaline saline solutions, including seawater, the chlorido- complexes still dominate the speciation of CdII because of the relatively low stability of CdCO3(aq). In contrast, the speciation of CuII [2007PBa] and PbII [2009PBa] in seawater is dominated by the respective species MCO3(aq). There is scope for additional high-quality measurements in the Cd2+ + H+ + CO32– system as the large uncertainties in the stability constants for the Cd2+-carbonato complexes significantly affect the speciation calculations.

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Kong, Fang, Qi-Pu Lin, Fei-Yan Yi, and Jiang-Gao Mao. "Explorations of New Phases in the GaIII/InIII-CuII-SeIV-O System." Inorganic Chemistry 48, no. 14 (2009): 6794–803. http://dx.doi.org/10.1021/ic900756u.

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Wang, Ya-Zhen, Wan-Hua Chen, and Sheng-Shui hu. "Study of a Novel [CuII(TPP)]/Nafion Film Electrode for the Detection of Nitric Oxide Radical (NO)." Collection of Czechoslovak Chemical Communications 71, no. 5 (2006): 698–708. http://dx.doi.org/10.1135/cccc20060698.

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A novel modified platinum electrode coated with copper(II)-5,10,15,20-tetraphenylporphyrin, [CuII(TPP)], has been developed. The electrochemical behavior of NO at the modified electrode was studied by cyclic and differential pulse voltammetries. In a deoxygenated phosphate-buffered saline solution (pH 7.4), the [CuII(TPP)]/Nafion-modified Pt electrode exhibits a strong electrocatalytic effect and stability to oxidation with NO and can be employed as a NO sensor. In this system, the modification film is capable of removing some endogenous anionic electroactive substances in biological samples, such as nitrite and ascorbate. The oxidation currents increase linearly with the concentration of NO in the range 1.8 × 10-7-0.9 × 10-4 M. The detection limit is 2.0 × 10-8 M. The nitric oxide radical, released from sodium nitroprusside (SNP), was also determined using chronoamperometry in the presence of light.

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Tempesta, Jésio D., Fábio Faria Paiva, Leonildo A. Ferreira, et al. "Metallacrown of CeIIICuII5: Synthesis, Structural Characterization and Insights for Nanoparticles." Magnetochemistry 10, no. 12 (2024): 96. https://doi.org/10.3390/magnetochemistry10120096.

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The heterobimetallic 15-MC-5 metallacrown of formula [CeCu5(5mpzHA)5(NO3)(H2O)7]·2NO3·7H2O, designated MC-Ce, was synthesized using 5-methyl-2-pyrazinehydroxamic acid (5mpzHA) as a linker, reacting with CeIII and CuII salts under mild conditions. Single-crystal X-ray diffraction analysis reveals a crown-like [Cu5Ce(5mpzHA)5] core, characteristic of a 15-MC-5 system, with five CuII atoms at the rim of the crown and the CeIII ion occupying the dome of the crown, with water molecules, oxygen atoms and one nitrate anion filling the nine-coordination sphere around the CeIII ion, which exhibits a distorted spherical tricapped trigonal prism geometry. The thermogravimetric analysis evidences successive mass losses due to the removal of water molecules and decomposition of the structure after 217 °C, whereas the PXRD analysis of the thermal decomposition residue reveals the presence of copper and copper/cerium oxide particles. These nanocomposite materials were also synthesized using the metallacrown MC-Ce under a hydrothermal method in the presence of multi-walled carbon nanotubes (MWCNTs), affording insights that this metallacrown can act as a source precursor for the synthesis of these mixed cerium/copper oxide nanomaterials. The experimental χMT value in MC-Ce at room temperature is 3.175 cm3 mol−1 K, which is higher than the calculated one for one magnetically isolated CeIII plus five CuII ions, probably due to the antiferromagnetic interactions among CuII ions within the metallacrown hoop plus the thermal depopulation of JZ sublevels of CeIII ground state (5/2), which exhibit a small splitting under the anisotropic ligand field effects. The χMT decreases continuously until it reaches the value of 0.80 cm3 mol−1 K at 10 K, reinforcing the presence of intramolecular antiferromagnetic interactions.

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TSANG, Shui Ying, Shuk Ching TAM, Ian BREMNER, and Mark J. BURKITT. "Research communication copper-1,10-phenanthroline induces internucleosomal DNA fragmentation in HepG2 cells, resulting from direct oxidation by the hydroxyl radical." Biochemical Journal 317, no. 1 (1996): 13–16. http://dx.doi.org/10.1042/bj3170013.

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In view of the current speculation regarding the possible role of reactive oxygen species (ROS) in apoptosis, both under physiological conditions and in response to chemicals that promote their intracellular formation, the present investigation was undertaken to examine whether DNA fragmentation during oxidative stress results from endonuclease activity (apoptosis) or from direct attack by ROS. We report that the incubation of HepG2 cells (a human-derived hepatoma cell line) with the copper(II) complex of 1,10-phenanthroline, CuII(OP)2, results in internucleosomal DNA fragmentation, which is widely recognized as being a hallmark of apoptosis. DNA fragmentation did not occur at low temperature, but activity was restored by the addition of ascorbic acid. It is proposed that DNA fragmentation results from the direct attack of hydroxyl radicals upon DNA. Hydroxyl radicals are produced from oxygen by the redox-cycling of CuII(OP)2, which is supported by metabolic processes at normal temperature. At low temperature ascorbic acid provides an artificial cellular reducing environment, thereby restoring hydroxyl radical formation. These findings were confirmed by the detection of internucleosomal DNA fragmentation following the exposure of isolated chromatin to a biomimetic CuII(OP)2 redox-cycling system. We conclude that DNA laddering, the widely employed hallmark of apoptosis, is not unique to endonuclease activity and may also result from direct attack upon DNA by the hydroxyl radical.

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19

Zhang, Sheng, Qi Yang, Xiangyu Liu, et al. "A Series of Enthalpy/Entropy-Driven Reversible Dissolution/Reorganization Equilibriums in the System of Cu(NO3)2–HL–GdX3–H2O (HL=5-methylpyrazine-2-carboxylic acid; X=Cl, Br, NO3, ClO4)." Australian Journal of Chemistry 67, no. 11 (2014): 1679. http://dx.doi.org/10.1071/ch13675.

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Five coordination polymers, [Cu(L)2]n (1), {[Cu(L)(Cl)(H2O)]·H2O}2n (2), [KCu(L)(μ-Cl)2]n (3), [Cu(L)(Br)H2O]n (4), and {[Cu0.5(HL)(H2O)](NO3)·H2O}2n (5) (HL = 5-methylpyrazine-2-carboxylic acid) were obtained by reactions of a pyramidal CuII-containing ligand, {[Cu(L)2(H2O)]·3H2O}n (LCu), with Gd(ClO4)3·6H2O, GdCl3·6H2O, GdCl3·6H2O/KCl, GdBr3·6H2O, or Gd(NO3)3·6H2O in water. Structural analysis reveals that the structures of these compounds range from a 0D block to a 2D network with modification of the environment of the CuII ions compared with LCu. Interestingly, there occurred a series of reversible dissolution/reorganization equilibriums between the initial reactants and the final products 1–5, which were determined as enthalpy/entropy driven chemical equilibriums by single crystal X-ray diffraction and microcalorimetry. In addition, the thermal stability of 1–4 and the magnetic property of 2 are discussed.

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20

Iacopino, Daniela, Ledi Menabue, and Monica Saladini. "Crystallographic Study on Metal(II) Complexes with N-(2-Nitrophenylsulfonyl)glycine." Australian Journal of Chemistry 52, no. 8 (1999): 741. http://dx.doi.org/10.1071/ch99036.

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The interaction of MII ions (MII =Mn II, CoII, NiII, CuII, ZnII, CdII, PbII) with N-(2-nitrophenylsulfonyl)- glycine (NO2psglyH2) leads to the formation at acidic pH of the complex carboxylate-type M(NO2psgly- O)2.x H2O species. At higher pH the deprotonation reaction of the sulfonamide nitrogen takes place, leading to the formation of the M(NO2psgly-N,O).x H2O species where the ligand acts as a chelating agent toward the metal ion through the carboxylic oxygen and the deprotonated sulfonamide nitrogen. In ternary systems the addition of 2,2′-bipyridine (bpy) allows the deprotonation of the sulfonamide nitrogen also in presence of metal ions such as ZnII, CoII and NiII, which were inactive in the binary system, and the solid compounds isolated are in the M/bpy/L molar ratio 1 : 1 : 1 (MII = CuII , ZnII ) or 1 : 2 : 1(MII = CoII , NiII, CdII). Here we describe the crystal and molecular structures of NO2psglyH2 (1), [Pb(NO2psgly-N,O)]n (2), [Cd(bpy)2(NO2psgly-N,O)].H2O (3) and [Cu(bpy)(NO2psgly-N,O)(H2O)] (4).

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Kuklin, Mikhail S., and Antti J. Karttunen. "Evolutionary Algorithm-Based Crystal Structure Prediction of CuxZnyOz Ternary Oxides." Molecules 28, no. 16 (2023): 5986. http://dx.doi.org/10.3390/molecules28165986.

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Binary zinc(II) oxide (ZnO) and copper(II) oxide (CuO) are used in a number of applications, including optoelectronic and semiconductor applications. However, no crystal structures have been reported for ternary Cu-Zn-O oxides. In that context, we investigated the structural characteristics and thermodynamics of CuxZnyOz ternary oxides to map their experimental feasibility. We combined evolutionary crystal structure prediction and quantum chemical methods to investigate potential CuxZnyOz ternary oxides. The USPEX algorithm and density functional theory were used to screen over 4000 crystal structures with different stoichiometries. When comparing compositions with non-magnetic CuI ions, magnetic CuII ions, and mixed CuI-CuII compositions, the magnetic Cu2Zn2O4 system is thermodynamically the most favorable. At ambient pressures, the thermodynamically most favorable ternary crystal structure is still 2.8 kJ/mol per atom higher in Gibbs free energy compared to experimentally known binary phases. The results suggest that thermodynamics of the hypothetical CuxZnyOz ternary oxides should also be evaluated at high pressures. The predicted ternary materials are indirect band gap semiconductors.

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Mailhot, Gilles, and Michèle Bolte. "Bimetallic systems for acrylamide photosensitized polymerization Part II. CrVICuII, a suitable system to control the polymerization process." Journal of Photochemistry and Photobiology A: Chemistry 56, no. 2-3 (1991): 387–96. http://dx.doi.org/10.1016/1010-6030(91)80040-o.

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M., L. Hari Kumaran Nair, and Shamla L. "Synthesis, spectral and thermal studies of copper(II) complexes of azodyes derived from 2,3-dimethyl-1-phenyl-4-amino-5-pyrazolone." Journal of Indian Chemical Society Vol. 86, Feb 2009 (2009): 133–38. https://doi.org/10.5281/zenodo.5807388.

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Department of Chemistry, University College, Thiruvananthapuram-695 034, Kerala, India E-mail: drmlhnair@gmail.com Manuscript received 11 January 2008, revised 14 July 2008, accepted 21 October 2008 Some novel metal complexes of copper(II) with azodyes derived from 4-aminoantipyrine and p-bromophenol have been synthesized and characterized by elemental analysis, IR, UV- Visible and ESR spectra, thermal studies, magnetic and conductance measurements. The X-ray diffraction patterns of the complex [Cu(PBPAAP)(NCS)(CI)] (where PBPAAP = parabromophenolazoantipyrine) have been examined and were indexed. The results show that the complex belongs to the orthorhombic crystal system with unit cell dimensions : a = 7.21 Á, b = 9.77 Á and c = 12.65 Á. The ligands are found to behave in a neutral bidentatc manner. The X·hand ESR spectra of the complex [Cu(PBPAAP)(CH3COO)2] shows an axial ligand field symmetry. All the complexes show square planar geometry with magnetic moments ranging from 1.79 to 1.85 B.M.

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24

Datta, Amitabha, Jui-Hsien Huang, Jack Clegg, Pei-Hsin Liu, and Sheng-Jie Chuang. "Octahedral CuII and NiII complexes manifesting with N′-[1-(pyridin-2-yl)ethylidene] acetohydrazide: Structural outlooks and spectral characteristics." Open Chemistry 11, no. 1 (2013): 116–22. http://dx.doi.org/10.2478/s11532-012-0141-z.

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AbstractA tridentate hydrazone precursor, N′-[1-(pyridin-2-yl)ethylidene]acetohydrazide (L) (1:1 refluxed product of acetichydrazide and 2-acetylpyridine), produced two octahedral CuII and NiII derivatives, [CuL2]·NO3 (1) and [NiL2]·ClO4·H2O (2). Both are subjected to X-ray diffraction system, and structural investigation shows that the central metal atom (CuII or NiII) adopts a distorted octahedral geometry with N4O2 donor sets by coordination of a pair of independent hydrazone precursors. Besides X-ray study, IR and UV-vis spectra, thermal analysis and room temperature magnetic moments are utilized for establishing significant characteristics of both complexes. It is apparent that the M-Npyridine bonds are slightly longer than the M-Nimino bonds, Cu1-N1 and Cu1-N4 [2.300(2) and 2.038(2) Å] for 1 and Ni1-N1 and Ni1-N4 [2.075(2) and 2.084(1) Å] for 2, Cu1-N2 and Cu1-N5 [2.062(1) and 1.932(1) Å] for 1 and Ni1-N2 and Ni1-N5 [2.008(2) and 1.975(2) Å] for 2, respectively. As per our observation, the effective magnetic moment value (µeff) is found to be 1.77 B.M. for 1 and 3.06 BM for 2, respectively.

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25

Villamaina, Roberta, Federica Gramigni, Umberto Iacobone, et al. "The H2O Effect on Cu Speciation in Cu-CHA-Catalysts for NH3-SCR Probed by NH3 Titration." Catalysts 11, no. 7 (2021): 759. http://dx.doi.org/10.3390/catal11070759.

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The present work is focused on the effect of water on NH3 adsorption over Cu-CHA SCR catalysts. For this purpose, samples characterized by different SAR (SiO2/Al2O3) ratios and Cu loadings were studied under both dry and wet conditions. H2O adversely affects NH3 adsorption on Lewis acid sites (Cu ions) over all the tested catalysts, as indicated by the decreased NH3 desorption at low temperature during TPD. Interestingly, the NH3/Cu ratio, herein regarded as an index for the speciation of Cu cations, fell in the range of 3–4 (in the presence of gaseous NH3) or 1–2 (no gaseous NH3) in dry conditions, in line with the formation of different NH3-solvated Cu species (e.g., [CuII(NH3)4]2+ and [CuII(OH)(NH3)3]+ with gaseous NH3, [Z2CuII(NH3)2]2+ and [ZCuII(OH)(NH3)]+ without gaseous NH3). When H2O was fed to the system, on the contrary, the NH3/Cu ratio was always close to 3 (or 1), while the Brønsted acidity was slightly increased. These results are consistent both with competition between H2O and NH3 for adsorption on Lewis sites and with the hydrolysis of a fraction of Z2CuII species into ZCuIIOH.

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Okubo, Takashi, Hiroyasu Kuwamoto, Kyung Ho Kim, et al. "Intervalence Charge-Transfer System by 1D Assembly of New Mixed-Valence Octanuclear CuI/CuII/CuIIICluster Units." Inorganic Chemistry 50, no. 7 (2011): 2708–10. http://dx.doi.org/10.1021/ic101794u.

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Sangita, Sharma, C. Shah Mayor, Patel Neha, J. Vora J., and Joshi J.D. "Studies on some ternary complexes of CuII with diamines and hydroxy acid." Journal of Indian Chemical Society Vol. 83, Jun 2006 (2006): 620–22. https://doi.org/10.5281/zenodo.5820083.

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Department of Chemistry, Hemchandracharya North Gujarat University, Patan-384 265, Gujarat, India Department of Chemistry, Gujarat Vidyapith, Sadra-382 320, Dist. Gandhinagar, Gujarat, India Department of Chemistry, Sardar Patel University, Vallabh Vidyanagar-388 120, Gujarat, India Manuscript received 27 May 2004, revised 28 November 2005, accepted 23 March 2006 Solution studies on ternary complexes of CuII with diamines (A) viz. ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, o-, m- or p-phenylenediamine and salicylic acid (HzL) in the ratio of 1 : 1 : 1 have been investigatedby pH metric technique at μ = 0.2 M (NaCIO4) and at temperature 30 ± 0.1 °C in aqueous media. The formation constant values for ternary system CuII-diamine-salicylic acid has been calculated and probable species like H2L, HL, CuALH, CuAL2 etc. are pruned with FORTRAN IV computer program. These values are discussed in terms of basicity of primary and secondary ligand, size of chelate ring, Δ log KT values and different statistical factors such as metal-ligand interaction, structure of ligands and intermolecular ligand-ligand interactions. Structure of complexes is suggested on the basis of molecular modeling.

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28

Butsch, Katharina, Alexander Haseloer, Simon Schmitz, Ingo Ott, Julia Schur, and Axel Klein. "FeIII, CuII and ZnII Complexes of the Rigid 9-Oxido-phenalenone Ligand—Spectroscopy, Electrochemistry, and Cytotoxic Properties." International Journal of Molecular Sciences 22, no. 8 (2021): 3976. http://dx.doi.org/10.3390/ijms22083976.

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The three complexes [Fe(opo)3], [Cu(opo)2], and [Zn(opo)2] containing the non-innocent anionic ligand opo− (opo− = 9-oxido-phenalenone, Hopo = 9-hydroxyphenalonone) were synthesised from the corresponding acetylacetonates. [Zn(opo)2] was characterised using 1H nuclear magnetic resonance (NMR) spectroscopy, the paramagnetic [Fe(opo)3] and [Cu(opo)2] by electron paramagnetic resonance (EPR) spectroscopy. While the EPR spectra of [Cu(opo)2] and [Cu(acac)2] in dimethylformamide (DMF) solution are very similar, a rather narrow spectrum was observed for [Fe(opo)3] in tetrahydrofuran (THF) solution in contrast to the very broad spectrum of [Fe(acac)3] in THF (Hacac = acetylacetone, 2,4-pentanedione; acac− = acetylacetonate). The narrow, completely isotropic signal of [Fe(opo)3] disagrees with a metal-centred S = 5/2 spin system that is observed in the solid state. We assume spin-delocalisation to the opo ligand in the sense of an opo− to FeIII electron transfer. All compounds show several electrochemical opo-centred reduction waves in the range of −1 to −3 V vs. the ferrocene/ferrocenium couple. However, for CuII and FeIII the very first one-electron reductions are metal-centred. Electronic absorption in the UV to vis range are due to π–π* transitions in the opo core, giving Hopo and [Zn(opo)2] a yellow to orange colour. The structured bands ranging from 400 to 500 for all compounds are assigned to the lowest energy π−π* transitions. They show markedly higher intensities and slight shifts for the CuII (brown) and FeIII (red) complexes and we assume admixing metal contributions (MLCT for CuII, LMCT for FeIII). For both complexes long-wavelength absorptions assignable to d–d transitions were detected. Detailed spectroelectrochemical experiments confirm both the electrochemical and the optical assignments. Hopo and the complexes [Cu(opo)2], [Zn(opo)2], and [Fe(opo)3] show antiproliferative activities against HT-29 (colon cancer) and MCF-7 (breast cancer) cell lines in the range of a few µM, comparable to cisplatin under the same conditions.

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29

Cañón-Mancisidor, Walter, Patricio Hermosilla-Ibáñez, Evgenia Spodine, Verónica Paredes-García, Carlos J. Gómez-García, and Diego Venegas-Yazigi. "Spin Frustrated Pyrazolato Triangular CuII Complex: Structure and Magnetic Properties, an Overview." Magnetochemistry 9, no. 6 (2023): 155. http://dx.doi.org/10.3390/magnetochemistry9060155.

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The synthesis and structural characterization of a new triangular Cu3–μ3OH pyrazolato complex of formula, [Cu3(μ3−OH)(pz)3(Hpz)3][BF4]2 (1−Cu3), Hpz = pyrazole, is presented. The triangular unit forms a quasi-isosceles triangle with Cu–Cu distances of 3.3739(9), 3.3571(9), and 3.370(1) Å. This complex is isostructural to the hexanuclear complex [Cu3(μ3−OH)(pz)3(Hpz)3](ClO4)2]2 (QOPJIP). A comparative structural analysis with other reported triangular Cu3–μ3OH pyrazolato complexes has been carried out, showing that, depending on the pyrazolato derivative, an auxiliary ligand or counter-anion can affect the nuclearity and/or the dimensionality of the system. The magnetic properties of 1−Cu3 are analyzed using experimental data and DFT calculation. A detailed analysis was performed on the magnetic properties, comparing experimental and theoretical data of other molecular triangular Cu3–μ3OH complexes, showing that the displacement of the μ3−OH− from the Cu3 plane, together with the type of organic ligands, influences the nature of the magnetic exchange interaction between the spin-carrier centers, since it affects the overlap of the magnetic orbitals involved in the exchange pathways. Finally, a detailed comparison of the magnetic properties of 1−Cu3 and QOPJIP was carried out, which allowed us to understand the differences in their magnetic properties.

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30

Powell, Kipton J., Paul L. Brown, Robert H. Byrne, et al. "Chemical speciation of environmentally significant metals with inorganic ligands. Part 5: The Zn2+ + OH–, Cl–, CO32–, SO42–, and PO43– systems (IUPAC Technical Report)." Pure and Applied Chemistry 85, no. 12 (2013): 2249–311. http://dx.doi.org/10.1351/pac-rep-13-06-03.

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The numerical modeling of ZnII speciation amongst the environmental inorganic ligands Cl&ndash;, OH&ndash;, CO32&ndash;, SO42&ndash;, and PO43&ndash; requires reliable values for the relevant stability (formation) constants. This paper compiles and provides a critical review of these constants and related thermodynamic data. It recommends values of log10&beta;p,q,r&deg; valid at Im = 0 mol&middot;kg&ndash;1 and 25 &deg;C (298.15 K), and reports the empirical reaction ion interaction coefficients, ∆&epsilon;, required to calculate log10&beta;p,q,r values at higher ionic strengths using the Br&oslash;nsted&ndash;Guggenheim&ndash;Scatchard specific ion interaction theory (SIT). Values for the corresponding reaction enthalpies, ∆rH, are reported where available. There is scope for additional high-quality measurements for the Zn2+ + H+ + CO32&ndash; system and for the Zn2+ + OH&ndash; and Zn2+ + SO42&ndash; systems at I &gt; 0. In acidic and weakly alkaline fresh water systems (pH &lt; 8), in the absence of organic ligands (e.g., humic substances), ZnII speciation is dominated by Zn2+(aq). In this respect, ZnII contrasts with CuII and PbII (the subjects of earlier reviews in this series) for which carbonato- and hydroxido- complex formation become important at pH &gt; 7. The speciation of ZnII is dominated by ZnCO3(aq) only at pH &gt; 8.4. In seawater systems, the speciation at pH = 8.2 is dominated by Zn2+(aq) with ZnCl+, Zn(Cl)2(aq), ZnCO3(aq), and ZnSO4(aq) as minor species. This behaviour contrasts with that for CuII and PbII for which at the pH of seawater in equilibrium with the atmosphere at 25 &deg;C (log10 {[H+]/c&deg;} &asymp; 8.2) the MCO3(aq) complex dominates over the MCln(2&ndash;n)+ species. The lower stability of the different complexes of ZnII compared with those of CuII, PbII, and CdII is also illustrated by the percentage of uncomplexed M2+ in seawater, which is ca. 55, 3, 2, and 3.3 % of [MII]T, respectively.

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31

Jurić, Marijana, Pavica Planinić, Nevenka Brničević, et al. "New Heterometallic (CuII and CrIII) Complexes – First Crystal Structure of an Oxalate-Bridged Ferromagnetically Coupled [CuIICrIIICuII] System." European Journal of Inorganic Chemistry 2006, no. 13 (2006): 2701–10. http://dx.doi.org/10.1002/ejic.200501092.

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32

Shuaib, Nadia M., and Mohamed S. El-Ezaby. "Complexes of vitamin B6—part XXII. The interaction of vitamin B6 compounds with CUII-glycinehydroxamic acid binary system." Polyhedron 14, no. 13-14 (1995): 1965–79. http://dx.doi.org/10.1016/0277-5387(94)00456-o.

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33

Sabbatini, Alessandra, Luísa M. D. R. S. Martins, Kamran T. Mahmudov, et al. "Microwave-assisted and solvent-free peroxidative oxidation of 1-phenylethanol to acetophenone with a CuII–TEMPO catalytic system." Catalysis Communications 48 (March 2014): 69–72. http://dx.doi.org/10.1016/j.catcom.2014.01.024.

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34

El-khalafy, S., S. El-din Etaiw, and M. Hassanein. "Catalytic activity of CuI/CuII cyanide based phenanthroline-bicarbonate system for enhancing aerobic oxidation of 2,6-di-tert-butylphenol." Journal of Saudi Chemical Society 26, no. 3 (2022): 101466. http://dx.doi.org/10.1016/j.jscs.2022.101466.

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35

Bravo-García, Laura, Gotzone Barandika, Arkaitz Fidalgo-Marijuan, et al. "Thermal and Magnetic Diversity in the Behaviour of the CuII-bdc-bpa System: 1D, 2D and Interpenetrated 3D Frameworks." European Journal of Inorganic Chemistry 2016, no. 29 (2016): 4783–91. http://dx.doi.org/10.1002/ejic.201600683.

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36

Abdulmalic, Mohammad A., Saddam Weheabby, Francois E. Meva, et al. "Probing the magnetic superexchange couplings between terminal CuII ions in heterotrinuclear bis(oxamidato) type complexes." Beilstein Journal of Nanotechnology 8 (April 6, 2017): 789–800. http://dx.doi.org/10.3762/bjnano.8.82.

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The reaction of one equivalent of [n-Bu4N]2[Ni(opboR2)] with two equivalents of [Cu(pmdta)(X)2] afforded the heterotrinuclear CuIINiIICuII containing bis(oxamidato) type complexes [Cu2Ni(opboR2)(pmdta)2]X2 (R = Me, X = NO3 – (1); R = Et, X = ClO4 – (2); R = n-Pr, X = NO3 – (3); opboR2 = o-phenylenebis(NR-substituted oxamidato); pmdta = N,N,N’,N”,N”-pentamethyldiethylenetriamine). The identities of the heterotrinuclear complexes 1–3 were established by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction studies, which revealed the cationic complex fragments [Cu2Ni(opboR2)(pmdta)2]2+ as not involved in any further intermolecular interactions. As a consequence thereof, the complexes 1–3 possess terminal paramagnetic [Cu(pmdta)]2+ fragments separated by [NiII(opboR2)]2– bridging units representing diamagnetic S Ni = 0 states. The magnetic field dependence of the magnetization M(H) of 1–3 at T = 1.8 K has been determined and is shown to be highly reproducible with the Brillouin function for an ideal paramagnetic spin = 1/2 system, verifying experimentally that no magnetic superexchange couplings exists between the terminal paramagnetic [Cu(pmdta)]2+ fragments. Susceptibility measurements versus temperature of 1–3 between 1.8–300 K were performed to reinforce the statement of the absence of magnetic superexchange couplings in these three heterotrinuclear complexes.

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37

Priyanka, Tiwari, C. Vishwakarma Mahesh, K. Joshi S., Kumar Rajesh, and S. Bhandari N. "Equilibrium and thermodynamic studies of PbII, CuII and ZnII adsorption onto Artemisia vulgarise (Paati) leaves." Journal of Indian Chemical Society Vol. 94, Jan 2017 (2017): 59–66. https://doi.org/10.5281/zenodo.5603539.

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Department of Chemistry, Kumaun University, S. S. J. Campus, Almora-263 601, Uttarakhand, India E-mail : dr.s.k.joshi.alm@gmail.com, im_nsbhandari@yahoo.co.in Department of Chemistry, L. S. M. P.G. College, Pithoragarh, Uttarakhand, India Manuscript received online 13 August 2016, accepted 01 October 2016 In the present study Artemisia vulgarise leaves (AVL) were used for removal of CuII, ZnII and PbII ions from aqueous solution. The plant Artemisia vulgarise is locally known as Paati. The investigation is carried out in a batch system with respect to adsorbent dose, pH, temperature, contact time, and initial metal ion concentration. The optimum adsorption conditions obtained were at contact time 75 min, pH 5, initial metal ion concentration 10 mg/L, temperature 15 ºC and adsorbent dose 1.5 g for copper and 2 g for zinc and lead. The adsorption process is described by Langmuir, Freundlich and Temkin models. Langmuir isotherm model provided a better fit with the experimental data than the Freundlich and Temkin isotherm. The results of the thermodynamic investigations indicated that the adsorption reactions were spontaneous (∆Gº < 0), feasible and exothermic (∆Hº < 0).

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38

(MISS), S. PATNAIK, and PANDA C. "Studies on Complex Formation of Zinc-, Copper-, Nickel-, Cobalt- and Manganese(II) with D(+)-Saccharic Acid." Journal of Indian Chemical Society Vol. 74, Mar 1997 (1997): 216–17. https://doi.org/10.5281/zenodo.5885959.

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Chemistry Department, Regional Engineering College. Rourkela-769 008 Manuscript received 16 December 1994, revised 6 July 1995, accepted 20 November 1995 Studies on Complex Formation of Zinc-, Copper-, Nickel-, Cobalt- and Manganese(II) with D(+)-Saccharic Acid.

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39

Yang, En-Cui, Zhong-Yi Liu, Li-Na Zhao, You-Li Yang, Cui-Hua Zhang, and Xiao-Jun Zhao. "Ligand-deprotonation induced structural diversity in a ternary CuII-triazole-tetracarboxylate self-assembly system: Synthesis, crystal structures, and magnetic behavior." CrystEngComm 13, no. 17 (2011): 5401. http://dx.doi.org/10.1039/c1ce05396e.

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40

Leech, Michael A., Judith A. K. Howard, Slimane Dahaoui, Nayan K. Solanki, and Malcolm A. Halcrow. "A solid-state phase transition at 41 K involving the cooperative ordering of a fluxional pseudo-Jahn–Teller CuII system." Chemical Communications, no. 22 (1999): 2245–46. http://dx.doi.org/10.1039/a906876g.

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41

Yang, Shi-Yao, La-Sheng Long, Rong-Bin Huang, Lan-Sun Zheng, and Seik Weng Ng. "Hydroxylation of isophthalic acid in the hydrothermal reaction of CuII-isophthalate system – Syntheses and crystal structures of two coordination polymers." Inorganica Chimica Acta 358, no. 6 (2005): 1882–86. http://dx.doi.org/10.1016/j.ica.2004.12.048.

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42

Praveen, P. Singh, Kumar Pramod, K. Nigam V., and K. P. Singh R. "Ionophoretic technique in the study of biologically important mixed complexes in solution (The system FeIII/CuII/NiII/CoII-cystine-NTA)." Journal of Indian Chemical Society Vol. 89, Oct 2012 (2012): 1323–27. https://doi.org/10.5281/zenodo.5769792.

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Electrochemical Laboratory of Green Synthesis, Department of Chemistry, University of Allahabad, Allahabad-211 002, Uttar Pradesh, India E-mail : rkp.singh@rediffmail.com Manuscript received 19 May 2011, revised 27 January 2012, accepted 01 February 2012 In the present communication ionophoretic technique has been used for the study of FeIII, CuII, NiII , CoII- cystine binary and FellI, CuII , NiII , ColI-cystine-NTA (nitrilotriacetic acid) mixed complexes. The stability constants of metal-cystine binary complexes are found to be 107.80, 106.90, 105.10, 104.66 and the stability constants of metal-cystine-NTA mixed complexes have been found to be 105.18, 104.88, 104.76, 104.10 for FeIII, CuII , NiII and CoII complexes respectively at µ= 0.1 M (HCIO4) and 25 ºC.

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43

Llano-Tomé, Francisco, Begoña Bazán, M. Karmele Urtiaga, et al. "Water-induced phase transformation of a CuII coordination framework with pyridine-2,5-dicarboxylate and di-2-pyridyl ketone: synchrotron radiation analysis." CrystEngComm 17, no. 33 (2015): 6346–54. http://dx.doi.org/10.1039/c5ce01033k.

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44

S., S. Chavan, and P. Hankare P. "X-Ray diffraction studies of NiII, CuII and ZnII complexes with 2-[2'-hydroxysalicylidene-5' -(2"-thiazolylazo.)]phenol." Journal of Indian Chemical Society Vol. 82, Jun 2005 (2005): 494–96. https://doi.org/10.5281/zenodo.5830440.

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Department of Chemistry, Shivaji University, Kolhapur-416 004, India E-mail : sanjaycha2@yahoo.com Manuscript received 17 October 2003, revised 13 August 2004, accepted 2 March 2005 The metal complexes of the type [ML(H2O)2]2 (where M = NiII , CuII and ZnII and H2L = 2-[2'-hydroxysalicylidene-5'-(2"- thiazolylazo)] phenol have been synthesized and subjected to the X-ray diffractometry to elucidate structural information. The structure of the complexes are found to be tetragonal belonging to non-primitive system. The strain broadening effects are also examined and discussed.

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45

Khan, Asfandyar, Zsolt Valicsek, and Ottó Horváth. "Photocatalytic Degradation of Rhodamine B in Heterogeneous and Homogeneous Systems." Hungarian Journal of Industry and Chemistry 49, no. 1 (2021): 9–16. http://dx.doi.org/10.33927/hjic-2021-02.

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This study focuses on the photocatalytic degradation of Rhodamine B (RhB) in heterogeneous and homogeneous photo-Fenton reactions. In the heterogeneous system, iron(II) doped copper ferrite CuII(x)FeII(1-x)FeIII2O4 nanoparticles (NPs) prepared in our previous work were employed as potential catalysts. The photodegradation of RhB was carried out in a quartz cuvette located in a diode array spectrometer. The experimental conditions such as pH, NPs dosage and H2O2 dosage with regard to the photocatalytic degradation of RhB were optimized to be 7.5, 500 mg/L and 8.9x10-2 mol/L, respectively. In addition, visible light-induced photodegradation of RhB was also carried out by using \ch{H2O2} over a wide pH range in the absence of heterogeneous photocatalysts. It was observed that the reaction rate significantly increased above pH 10, resulting in a faster rate of degradation of RhB, which may be attributed to the deprotonation of hydrogen peroxide. Furthermore, the potential antibacterial property of such catalysts against the Gram-negative bacterium Vibrio fischeri in a bioluminescence assay yielded inhibition activities of more than 60% in all cases.

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46

Toikka, Yulia N., Dar’ya V. Spiridonova, Alexander S. Novikov, and Nadezhda A. Bokach. "Copper(II) Prevents the Saccarine-Dialkylcyanamide Coupling by Forming Mononuclear (Saccharinate)(Dialkylcyanamide)copper(II) Complexes." Inorganics 9, no. 9 (2021): 69. http://dx.doi.org/10.3390/inorganics9090069.

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The reaction in the system CuII/sacNa(H)/NCNR2 (sacNa(H) = sodium saccharinate (saccharin); R = Me, Et) results in the formation of the complexes [Cu(sac)2(NCNR2)(H2O)2] (R = Me 1, Et 2) instead of the expected products derived from the saccharin–cyanamide coupling. Complexes 1, 2, and hydrate 1·2H2O were characterized by IR, AAS (Cu%), TGA, and also by single-crystal X-ray diffraction for 1 and 1·2H2O. An integrated computational study of model structure 1 in the gas phase demonstrates that the Cu–Ncyanamide and Cu–Nsac coordination bonds exhibited a single bond character, polarized toward the N atom and almost purely electrostatic, with the calculated vertical total energies for the Cu–Ncyanamide and Cu–Nsac of 43.6 and 156.4 kcal/mol, respectively. These data confirmed that the copper(II) completely blocks the nucleophilic centers of ligands via coordination, thus preventing the saccharin–cyanamide coupling.

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47

Panina, Natalie Sergeevna, Alisher Talgatovich Talgatov, Roman Vladimirovich Suezov, Nicolay Leonidovich Medvedskiy, Aleksei Vladimirovich Eremin, and Alexandr Nicolaevich Belyaev. "Bi- and polynuclear coordination compounds of d-elements as catalysts of homogeneous selective oxidation of thiol groups." Mediterranean Journal of Chemistry 7, no. 3 (2018): 172–82. http://dx.doi.org/10.13171/mjc73181017-eremin.

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This research aims to study the catalytic cycle reactions for homogeneous selective oxidation of thiol RSH groups to RSSR with the participation of coordination compounds for d-element ions-NiII, PdII, Pt II, CuI , CuII. We used the DFT M06, PBE0 / Def2-TZVP methods to build the quantum chemical models of the reactions. We have developed a mechanism for the functioning of the catalytic system in which primary active centers are either binuclear {M(-OH)2M}n+ or polynuclear {M(μ-OH)2M(μ-OH)2M}2+ sites. Catalysts under consideration should retain stable spatial complementarity at all stages of the process. The main interrelated functions of the binuclear catalysts are the spatial approaching of anions RS– in the inner sphere of the bridged coordination compound required for the disulfide (–S–S–) cross-linking and the two-electron redox transfer during the transformation of these anions into disulfide (СH3)2S2

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48

ANIL, K. PANDEY, SABHAPATI, and NAYAN RAM. "Studies on some Binary and Ternary Complexes of Nickel(II)." Journal of Indian Chemical Society Vol. 64, May 1987 (1987): 274–76. https://doi.org/10.5281/zenodo.6218230.

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Department of Chemistry, Hindu. College (Rohilkhand University), Moradabad-244 001 Manuscript received 4 April 1986, revised 8 October 1986, accepted 22 April 1987 Potentiometric studies on binary and ternary complexes of NiII ion with 1,3-dihydroxy-4-(2'-pyridylazo)benzene (PAR, H2L), 1 -(2'-arsonophenylazo)-2.hydroxynaphthalene-3,6-disulphonic acid (APANS, H5L), pyrogallol sulphonphthalein (PGR, H4L), and with pairs of ligands ; PAR-ethylenediamine (en, A), APANS-en, PGR-en, PAR-1,10 phenanthroline (pn, A), APANS-pn, PGR-pn, have been carried out at 20° (µ=0.10 M KNO3). The experimental data analysed over a pH range 2.6 —11.0 show the formation of NiHL+, NiL, NiL(OH)-, Ni(HL)2 \(NiHL_2^-\), \(NiL_2^2-\), NiHLA+ (with PAR, en and pn) ; NILA(OH)- (with PAR and en) ; NiH2L-, NiHL2-, NiL2-, NiH2LA-, NiHLA2-, NiLA2- (with APANS, en and pn) ; NiH2L, NiHL-, NiL2-, Ni2L, Ni2L(OH)-, NiH2LA, NiHLA-, NiLA2- (with PGR and pn). The corresponding equilibrium constants [except the PAR complexes, NiHL+, Ni(HL)2, \(NiHL_2^-\), NiHLA+ (with en and pn), where precipitation of the reaction mixture did not allow calculation] have been evaluated and the results discussed.

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49

Powell, Kipton J., Paul L. Brown, Robert H. Byrne, et al. "Chemical speciation of environmentally significant metals with inorganic ligands. Part 3: The Pb2+ + OH–, Cl–, CO32–, SO42–, and PO43– systems (IUPAC Technical Report)." Pure and Applied Chemistry 81, no. 12 (2009): 2425–76. http://dx.doi.org/10.1351/pac-rep-09-03-05.

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Complex formation between PbII and the common environmental inorganic ligands, Cl–, OH–, CO32–, SO42–, and PO43–, can be significant in natural waters with low concentrations of organic matter. Numerical modeling of the speciation of PbII amongst these inorganic ligands requires reliable values for the relevant stability (formation) constants. This paper provides a critical review of such constants and related thermodynamic data. It recommends values of log10 βp,q,r° valid at Im = 0 mol kg–1 and 25 °C (298.15 K), along with the equations and empirical coefficients required to calculate log10βp,q,r values at higher ionic strengths using the Brønsted–Guggenheim–Scatchard specific ion interaction theory (SIT). Some values for reaction enthalpies, ΔrH, are also reported. In weakly acidic fresh water systems (–log10 {[H+]/c°} &lt; 6), the speciation of PbII is similar to that of CuII. In the absence of organic ligands, PbII speciation is dominated by Pb2+(aq), with PbSO4(aq) as a minor species. In weakly alkaline solutions, 8.0 &lt; –log10 {[H+]/c°} &lt; 9.0, the speciation is dominated by the carbonato species PbCO3(aq) and Pb(CO3)22–. In weakly acidic saline systems (–log10 {[H+]/c°} &lt; 6), the speciation is dominated by PbCln(2–n)+ complexes, (n = 0–3), with Pb2+(aq) as a minor species. In this medium (and in seawater), the speciation contrasts with that of CuII because of the higher stability of the Pb2+-chlorido- complexes. In seawater at –log10 {[H+]/c°} = 8.2, the calculated speciation is less well defined, although it is clearly dominated by the uncharged species PbCO3(aq) (41 % of [Pb]T) with a significant contribution (16 %) from Pb(CO3)Cl– and minor contributions (5–10 %) from PbCln(2–n)+, (n = 0–3) and Pb(CO3)22–. The uncertainty in calculations of PbII speciation in seawater arises from (a) the large uncertainty in the stability constant for the apparently dominant species PbCO3(aq), (b) the reliance on statistical predictions for stability constants of the ternary species Pb(CO3)Cl– and Pb(CO3)OH–, and (c) the uncertainty in the stability constant for PbCl42–, the available value being considered "indicative" only. There is scope for additional detailed high-quality measurements in the Pb2+ + CO32– + Cl– system.

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Kim, Soon Young, and Jong-In Hong. "Dual signal (color change and fluorescence ON–OFF) ensemble system based on bis(Dpa-CuII) complex for detection of PPi in water." Tetrahedron Letters 50, no. 17 (2009): 1951–53. http://dx.doi.org/10.1016/j.tetlet.2009.02.036.

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Journal articles on the topic 'CuII system'

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