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Julia Jezierska - One of the best experts on this subject based on the ideXlab platform.
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novel 1d and 2d heterometallic cu cd complexes comprising unique mixed anion cd μ cl μ o2cme cl o2cme 2 cd μ o2cme 2i o2cme 2 cd μ i μ o2cme i o2cme 2 and cd2 ncs 6 o2cme 22 building blocks synthesis from Elemental Copper structure and magnetism
Polyhedron, 2005Co-Authors: Oksana V. Nesterova, Vladimir N. Kokozay, Brian W. Skelton, Svitlana R. Petrusenko, Anna V Lipetskaya, Julia JezierskaAbstract:Abstract Three new Cu/Cd mixed-anion solid-state coordination polymers [Cu(en)2Cd(μ-Cl)(μ-O2CMe)Cl(O2CMe)]n (1), [Cu(en)2CdI1.64(O2CMe)2.36]n (2) and [Cu2(en)4Cd2(NCS)6(O2CMe)2]n (3) have been prepared using unactivated Copper powder, cadmium acetate, NH4X (X = Cl, I, NCS) and ethylenediamine in non-aqueous solvents, namely dmso, dmf and CH3OH, in the open air. Depending on the nature of the selected counter-anion in the initial ammonium salt, a facile approach to the controlled assembly of 1D or 2D extended networks has been offered. X-ray studies show that 1 and 2 possess 1D helical chain crystal structures, constituting cationic Cu ( en ) 2 2 + and mixed-ligand anionic Cd(μ-Cl)(μ-O2CMe)Cl(O2CMe)2−, Cd(μ-O2CMe)2I(O2CMe)2− or Cd(μ-I)(μ-O2CMe)I(O2CMe)2− building blocks, conjoining together through the oxygen atoms of chelating bidentate and simultaneously bridging unidentate acetate ligands and also by a bridging chlorine atom (for 1) and by a bridging iodine or oxygen atom of a weakly bidentate acetate group (for 2). In both complexes, distinct hydrogen bonds are present and serve to increase the dimensionality of the compound from one to two. The 2D polymeric sheet of complex 3 consists of a 1D mixed-anion polymer –NCS–Cd(NCS)2(O2CMe)–SCN–Cd(NCS)2(O2CMe)–NCS– and Cu(en)2 units. Each of two crystallographically independent cadmium atoms has six coordination, consisting of CdN4O2 or CdS2N2O2 distorted octahedral geometries. The Copper atom of Cu(en)2 also exhibits a distorted octahedral arrangement. Apical bonds between the Cu(II) and S atoms from terminal NCS–groups [3.1113(12) and 3.1467(14) A] link the anionic chains forming a 2D network. Variable-temperature magnetic susceptibility measurements of 1–3 show weak antiferromagnetic coupling between the Copper centres.
Oksana V. Nesterova - One of the best experts on this subject based on the ideXlab platform.
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novel 1d and 2d heterometallic cu cd complexes comprising unique mixed anion cd μ cl μ o2cme cl o2cme 2 cd μ o2cme 2i o2cme 2 cd μ i μ o2cme i o2cme 2 and cd2 ncs 6 o2cme 22 building blocks synthesis from Elemental Copper structure and magnetism
Polyhedron, 2005Co-Authors: Oksana V. Nesterova, Vladimir N. Kokozay, Brian W. Skelton, Svitlana R. Petrusenko, Anna V Lipetskaya, Julia JezierskaAbstract:Abstract Three new Cu/Cd mixed-anion solid-state coordination polymers [Cu(en)2Cd(μ-Cl)(μ-O2CMe)Cl(O2CMe)]n (1), [Cu(en)2CdI1.64(O2CMe)2.36]n (2) and [Cu2(en)4Cd2(NCS)6(O2CMe)2]n (3) have been prepared using unactivated Copper powder, cadmium acetate, NH4X (X = Cl, I, NCS) and ethylenediamine in non-aqueous solvents, namely dmso, dmf and CH3OH, in the open air. Depending on the nature of the selected counter-anion in the initial ammonium salt, a facile approach to the controlled assembly of 1D or 2D extended networks has been offered. X-ray studies show that 1 and 2 possess 1D helical chain crystal structures, constituting cationic Cu ( en ) 2 2 + and mixed-ligand anionic Cd(μ-Cl)(μ-O2CMe)Cl(O2CMe)2−, Cd(μ-O2CMe)2I(O2CMe)2− or Cd(μ-I)(μ-O2CMe)I(O2CMe)2− building blocks, conjoining together through the oxygen atoms of chelating bidentate and simultaneously bridging unidentate acetate ligands and also by a bridging chlorine atom (for 1) and by a bridging iodine or oxygen atom of a weakly bidentate acetate group (for 2). In both complexes, distinct hydrogen bonds are present and serve to increase the dimensionality of the compound from one to two. The 2D polymeric sheet of complex 3 consists of a 1D mixed-anion polymer –NCS–Cd(NCS)2(O2CMe)–SCN–Cd(NCS)2(O2CMe)–NCS– and Cu(en)2 units. Each of two crystallographically independent cadmium atoms has six coordination, consisting of CdN4O2 or CdS2N2O2 distorted octahedral geometries. The Copper atom of Cu(en)2 also exhibits a distorted octahedral arrangement. Apical bonds between the Cu(II) and S atoms from terminal NCS–groups [3.1113(12) and 3.1467(14) A] link the anionic chains forming a 2D network. Variable-temperature magnetic susceptibility measurements of 1–3 show weak antiferromagnetic coupling between the Copper centres.
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A new 2D heterometallic Cu/Cd mixed-anion polymer with dicyanamide and thiocyanate bridges formed via the reaction of Elemental Copper, cadmium dicyanamide and ethylenediamine
Inorganic Chemistry Communications, 2004Co-Authors: Oksana V. Nesterova, Vladimir N. Kokozay, Brian W. Skelton, Svitlana R. Petrusenko, Wolfgang LinertAbstract:Abstract The new heterometallic 2D polymer [Cu(en)2Cd(dca)2(SCN)2]n (en=ethylenediamine; dca=dicyanamide, N(CN)2−), the first example of a compound containing the unique mixed-anion Cd(dca)2(SCN)22− fragment, has been prepared from Copper powder, cadmium dicyanamide, ammonium thiocyanate and ethylenediamine in methanol solution in air. The polymeric sheets of the compound comprise two different rings – 28-membered [Cu2Cd4(μ1,5-dca)2(μ1,3-NCS)4] macrocycles in which two 12-membered [Cd2(μ1,5-dca)2] rings form sections.
Vladimir N. Kokozay - One of the best experts on this subject based on the ideXlab platform.
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novel 1d and 2d heterometallic cu cd complexes comprising unique mixed anion cd μ cl μ o2cme cl o2cme 2 cd μ o2cme 2i o2cme 2 cd μ i μ o2cme i o2cme 2 and cd2 ncs 6 o2cme 22 building blocks synthesis from Elemental Copper structure and magnetism
Polyhedron, 2005Co-Authors: Oksana V. Nesterova, Vladimir N. Kokozay, Brian W. Skelton, Svitlana R. Petrusenko, Anna V Lipetskaya, Julia JezierskaAbstract:Abstract Three new Cu/Cd mixed-anion solid-state coordination polymers [Cu(en)2Cd(μ-Cl)(μ-O2CMe)Cl(O2CMe)]n (1), [Cu(en)2CdI1.64(O2CMe)2.36]n (2) and [Cu2(en)4Cd2(NCS)6(O2CMe)2]n (3) have been prepared using unactivated Copper powder, cadmium acetate, NH4X (X = Cl, I, NCS) and ethylenediamine in non-aqueous solvents, namely dmso, dmf and CH3OH, in the open air. Depending on the nature of the selected counter-anion in the initial ammonium salt, a facile approach to the controlled assembly of 1D or 2D extended networks has been offered. X-ray studies show that 1 and 2 possess 1D helical chain crystal structures, constituting cationic Cu ( en ) 2 2 + and mixed-ligand anionic Cd(μ-Cl)(μ-O2CMe)Cl(O2CMe)2−, Cd(μ-O2CMe)2I(O2CMe)2− or Cd(μ-I)(μ-O2CMe)I(O2CMe)2− building blocks, conjoining together through the oxygen atoms of chelating bidentate and simultaneously bridging unidentate acetate ligands and also by a bridging chlorine atom (for 1) and by a bridging iodine or oxygen atom of a weakly bidentate acetate group (for 2). In both complexes, distinct hydrogen bonds are present and serve to increase the dimensionality of the compound from one to two. The 2D polymeric sheet of complex 3 consists of a 1D mixed-anion polymer –NCS–Cd(NCS)2(O2CMe)–SCN–Cd(NCS)2(O2CMe)–NCS– and Cu(en)2 units. Each of two crystallographically independent cadmium atoms has six coordination, consisting of CdN4O2 or CdS2N2O2 distorted octahedral geometries. The Copper atom of Cu(en)2 also exhibits a distorted octahedral arrangement. Apical bonds between the Cu(II) and S atoms from terminal NCS–groups [3.1113(12) and 3.1467(14) A] link the anionic chains forming a 2D network. Variable-temperature magnetic susceptibility measurements of 1–3 show weak antiferromagnetic coupling between the Copper centres.
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A new 2D heterometallic Cu/Cd mixed-anion polymer with dicyanamide and thiocyanate bridges formed via the reaction of Elemental Copper, cadmium dicyanamide and ethylenediamine
Inorganic Chemistry Communications, 2004Co-Authors: Oksana V. Nesterova, Vladimir N. Kokozay, Brian W. Skelton, Svitlana R. Petrusenko, Wolfgang LinertAbstract:Abstract The new heterometallic 2D polymer [Cu(en)2Cd(dca)2(SCN)2]n (en=ethylenediamine; dca=dicyanamide, N(CN)2−), the first example of a compound containing the unique mixed-anion Cd(dca)2(SCN)22− fragment, has been prepared from Copper powder, cadmium dicyanamide, ammonium thiocyanate and ethylenediamine in methanol solution in air. The polymeric sheets of the compound comprise two different rings – 28-membered [Cu2Cd4(μ1,5-dca)2(μ1,3-NCS)4] macrocycles in which two 12-membered [Cd2(μ1,5-dca)2] rings form sections.
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novel heterometallic cu cd complex containing a unique polymeric ladder like anion cd2 o2cme 6 2 n derived from Elemental Copper and cadmium oxide
Inorganic Chemistry Communications, 2003Co-Authors: Oksana V Pryma, Vladimir N. Kokozay, Svitlana R. Petrusenko, Oleg V Shishkin, Marina V ZhigalkoAbstract:Abstract Copper powder reacts with cadmium oxide and ammonia acetate in methanol solution of ethylenediamine affording {[Cu(en)2][Cd2(O2CMe)6]}n in which seven-coordinated cadmium atoms are ligated by three bonding modes of acetate groups forming ladder-like anions [Cd2(O2CMe)6]2−n. The cations [Cu(en)2]2+ are located in the lattice and serve as bridges to connect separate anionic polymer chains into a two- dimensional network via hydrogen bonds.
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A novel heterometallic μ4-oxo-bridged complex based on an octahedral Cd2Cu4 skeleton via the reaction of Elemental Copper, cadmium acetate and amino alcohol
Inorganic Chemistry Communications, 2003Co-Authors: Elena A. Vinogradova, Vladimir N. Kokozay, Olga Yu. Vassilyeva, Brian W. SkeltonAbstract:The reaction of Copper powder in dmso with cadmium acetate hydrate and 2-dimethylaminoethanol (HL), in open air, afforded [Cd 2 Cu 4 (μ 4 -O)(O 2 CMe) 6 L 4 ]·2H 2 O with a metal skeleton that approximates an octahedron. The Copper atoms are tetrahedrally arranged about the oxygen atom in a considerably distorted fashion. The amino alkoxo and acetate ligands display a variety of bonding modes in the complex.
Svitlana R. Petrusenko - One of the best experts on this subject based on the ideXlab platform.
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novel 1d and 2d heterometallic cu cd complexes comprising unique mixed anion cd μ cl μ o2cme cl o2cme 2 cd μ o2cme 2i o2cme 2 cd μ i μ o2cme i o2cme 2 and cd2 ncs 6 o2cme 22 building blocks synthesis from Elemental Copper structure and magnetism
Polyhedron, 2005Co-Authors: Oksana V. Nesterova, Vladimir N. Kokozay, Brian W. Skelton, Svitlana R. Petrusenko, Anna V Lipetskaya, Julia JezierskaAbstract:Abstract Three new Cu/Cd mixed-anion solid-state coordination polymers [Cu(en)2Cd(μ-Cl)(μ-O2CMe)Cl(O2CMe)]n (1), [Cu(en)2CdI1.64(O2CMe)2.36]n (2) and [Cu2(en)4Cd2(NCS)6(O2CMe)2]n (3) have been prepared using unactivated Copper powder, cadmium acetate, NH4X (X = Cl, I, NCS) and ethylenediamine in non-aqueous solvents, namely dmso, dmf and CH3OH, in the open air. Depending on the nature of the selected counter-anion in the initial ammonium salt, a facile approach to the controlled assembly of 1D or 2D extended networks has been offered. X-ray studies show that 1 and 2 possess 1D helical chain crystal structures, constituting cationic Cu ( en ) 2 2 + and mixed-ligand anionic Cd(μ-Cl)(μ-O2CMe)Cl(O2CMe)2−, Cd(μ-O2CMe)2I(O2CMe)2− or Cd(μ-I)(μ-O2CMe)I(O2CMe)2− building blocks, conjoining together through the oxygen atoms of chelating bidentate and simultaneously bridging unidentate acetate ligands and also by a bridging chlorine atom (for 1) and by a bridging iodine or oxygen atom of a weakly bidentate acetate group (for 2). In both complexes, distinct hydrogen bonds are present and serve to increase the dimensionality of the compound from one to two. The 2D polymeric sheet of complex 3 consists of a 1D mixed-anion polymer –NCS–Cd(NCS)2(O2CMe)–SCN–Cd(NCS)2(O2CMe)–NCS– and Cu(en)2 units. Each of two crystallographically independent cadmium atoms has six coordination, consisting of CdN4O2 or CdS2N2O2 distorted octahedral geometries. The Copper atom of Cu(en)2 also exhibits a distorted octahedral arrangement. Apical bonds between the Cu(II) and S atoms from terminal NCS–groups [3.1113(12) and 3.1467(14) A] link the anionic chains forming a 2D network. Variable-temperature magnetic susceptibility measurements of 1–3 show weak antiferromagnetic coupling between the Copper centres.
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A new 2D heterometallic Cu/Cd mixed-anion polymer with dicyanamide and thiocyanate bridges formed via the reaction of Elemental Copper, cadmium dicyanamide and ethylenediamine
Inorganic Chemistry Communications, 2004Co-Authors: Oksana V. Nesterova, Vladimir N. Kokozay, Brian W. Skelton, Svitlana R. Petrusenko, Wolfgang LinertAbstract:Abstract The new heterometallic 2D polymer [Cu(en)2Cd(dca)2(SCN)2]n (en=ethylenediamine; dca=dicyanamide, N(CN)2−), the first example of a compound containing the unique mixed-anion Cd(dca)2(SCN)22− fragment, has been prepared from Copper powder, cadmium dicyanamide, ammonium thiocyanate and ethylenediamine in methanol solution in air. The polymeric sheets of the compound comprise two different rings – 28-membered [Cu2Cd4(μ1,5-dca)2(μ1,3-NCS)4] macrocycles in which two 12-membered [Cd2(μ1,5-dca)2] rings form sections.
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novel heterometallic cu cd complex containing a unique polymeric ladder like anion cd2 o2cme 6 2 n derived from Elemental Copper and cadmium oxide
Inorganic Chemistry Communications, 2003Co-Authors: Oksana V Pryma, Vladimir N. Kokozay, Svitlana R. Petrusenko, Oleg V Shishkin, Marina V ZhigalkoAbstract:Abstract Copper powder reacts with cadmium oxide and ammonia acetate in methanol solution of ethylenediamine affording {[Cu(en)2][Cd2(O2CMe)6]}n in which seven-coordinated cadmium atoms are ligated by three bonding modes of acetate groups forming ladder-like anions [Cd2(O2CMe)6]2−n. The cations [Cu(en)2]2+ are located in the lattice and serve as bridges to connect separate anionic polymer chains into a two- dimensional network via hydrogen bonds.
Jim A Field - One of the best experts on this subject based on the ideXlab platform.
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Elemental Copper nanoparticle toxicity to anaerobic ammonium oxidation and the influence of ethylene diamine tetra acetic acid edta on Copper toxicity
Chemosphere, 2017Co-Authors: Jorge Gonzalezestrella, Daniel Puyol, Reyes Sierraalvarez, Sarah E Neely, Jim A FieldAbstract:Abstract Soluble ions released by Elemental Copper nanoparticles (Cu 0 NP) are toxic to key microorganisms of wastewater treatment processes. However, their toxicity to anaerobic ammonium oxidation (anammox) has not yet been studied. Chelating agents occurring in wastewater may decrease Copper ions (Cu 2+ ) concentration and consequently, decrease Copper toxicity. This study evaluated Cu 0 NP and CuCl 2 toxicity to anammox and the influence of ethylene diamine-tetra acetic acid (EDTA) on Copper toxicity. Bioassays were supplemented with Cu 0 NP or CuCl 2 with and without EDTA. Anammox activities were used to calculate inhibition constants ( K i ). Results showed that Cu 0 NP are toxic to anammox. K i constants with respect to added Copper were 1.8- and 2.81-fold larger (less toxic) in EDTA-containing assays for Cu 0 NP and CuCl 2, respectively, compared to EDTA-free assays. Additionally, K i constants calculated in EDTA-free assays with respect the measured dissolved Copper concentration were 0.023 mM Cu 0 NP and 0.014 mM CuCl 2 . The similarity of these K i constants indicates that Cu 0 NP toxicity to anammox is caused by the release of Cu 2+ . Finally, severe toxicity caused by 0.315 mM and Cu 0 NP 0.118 mM CuCl 2 was attenuated by 88–100% when 0.14 mM EDTA was supplied. Toxicity attenuation likely occurred because EDTA complexed Cu 2+ ions, thus, decreasing their bioavailability. Overall, this study indicates that Cu 0 NP and CuCl 2 are toxic to anammox, and furthermore, that EDTA attenuates Cu 0 NP and CuCl 2 toxicity to anammox by complexing Cu 2+ ions.
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iron sulfide attenuates the methanogenic toxicity of Elemental Copper and zinc oxide nanoparticles and their soluble metal ion analogs
Science of The Total Environment, 2016Co-Authors: Jorge Gonzalezestrella, Sara Gallagher, Reyes Sierraalvarez, Jim A FieldAbstract:Elemental Copper (Cu(0)) and zinc oxide (ZnO) nanoparticle (NP) toxicity to methanogens has been attributed to the release of soluble metal ions. Iron sulfide (FeS) partially controls the soluble concentration of heavy metals and their toxicity in aquatic environments. Heavy metals displace the Fe from FeS forming poorly soluble metal sulfides in the FeS matrix. Therefore, FeS may be expected to attenuate the NP toxicity. This work assessed FeS as an attenuator of the methanogenic toxicity of Cu(0) and ZnO NPs and their soluble salt analogs. The toxicity attenuation capacity of fine (25-75μm) and coarse (500 to 1200μm) preparations of FeS (FeS-f and FeS-c respectively) was tested in the presence of highly inhibitory concentrations of CuCl2, ZnCl2 Cu(0) and ZnO NPs. FeS-f attenuated methanogenic toxicity better than FeS-c. The results revealed that 2.5× less FeS-f than FeS-c was required to recover the methanogenic activity to 50% (activity normalized to uninhibited controls). The results also indicated that a molar FeS-f/Cu(0) NP, FeS-f/ZnO NP, FeS-f/ZnCl2, and FeS-f/CuCl2 ratio of 2.14, 2.14, 4.28, and 8.56 respectively, was necessary to recover the methanogenic activity to >75%. Displacement experiments demonstrated that CuCl2 and ZnCl2 partially displaced Fe from FeS. As a whole, the results indicate that not all the sulfide in FeS was readily available to react with the soluble Cu and Zn ions which may explain the need for a large stoichiometric excess of FeS to highly attenuate Cu and Zn toxicity. Overall, this study provides evidence that FeS attenuates the toxicity caused by Cu(0) and ZnO NPs and their soluble ion analogs to methanogens.
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Elemental Copper nanoparticle toxicity to different trophic groups involved in anaerobic and anoxic wastewater treatment processes
Science of The Total Environment, 2015Co-Authors: Jorge Gonzalezestrella, Daniel Puyol, Sara Gallagher, Reyes Sierraalvarez, Jim A FieldAbstract:Elemental Copper nanoparticles (Cu(0) NPs) are potentially inhibitory to the different key microbial trophic groups involved in biological wastewater treatment processes. Cu-based NPs are known to be toxic to methanogens at low concentrations. However, very little is known about the toxic effect of Cu(0) NPs on other microbial groups involved in either upper trophic levels of anaerobic digestion or anoxic nitrogen removal processes. This study evaluated the toxicity of Cu(0) NPs to glucose fermentation, syntrophic propionate oxidation and denitrification in shaken batch bioassays with soluble substrates. Batch experiments were also supplemented with CuCl2 to evaluate the inhibitory impact of soluble Cu(II) ions. Syntrophic propionate oxidation and glucose fermentation were the least and most inhibited processes with inhibition constant (Ki) values of 0.202 and 0.047 mM of added Cu(0) NPs, respectively. Further analyses revealed that the Ki values calculated as a function of the free soluble Cu concentration were <0.003 mM for every biological process tested and most of these Ki values were similar in order of magnitude regardless of whether the Cu source was CuCl2 or Cu(0) NPs. The results taken as a whole indicate that Cu(0) NPs are toxic to all the microbial processes studied. Therefore, Cu(0) NPs can potentially be an important inhibitor of anaerobic wastewater treatment processes that rely on these trophic groups. The evidence suggests that the inhibitory impact of Cu(0) NPs was mainly due to the release of toxic Cu(II) ions originating from the corrosion and dissolution of Cu(0) NPs.