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1

Li, Yong Xi, Yong Fu Zhang et Kenneth J. Klabunde. « Spectroscopic characterization of platinum-tin bimetallic catalysts prepared by solvated metal atom dispersion (SMAD) ». Langmuir 4, no 2 (mars 1988) : 385–91. http://dx.doi.org/10.1021/la00080a022.

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Klabunde, K. J., Li Yong-Xi et K. F. Purcell. « Mössbauer and XPS studies of Pt−Sn catalysts prepared by solvated metal atom dispersion ». Hyperfine Interactions 41, no 1 (décembre 1988) : 649–52. http://dx.doi.org/10.1007/bf02400474.

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Yong-Xi, Li, et Kenneth J. Klabunde. « A study of Pt−Fe/Al2O3 catalysts prepared by solvated metal atom dispersion (SMAD) ». Hyperfine Interactions 41, no 1 (décembre 1988) : 665–68. http://dx.doi.org/10.1007/bf02400478.

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Li, Yong Xi, et Kenneth J. Klabunde. « Platinum-tin-alumina bimetallic catalysts prepared by solvated metal atom dispersion (SMAD). Synthesis and catalytic performance ». Langmuir 3, no 4 (juillet 1987) : 558–62. http://dx.doi.org/10.1021/la00076a021.

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LI, Y. « Studies of Pt-Sn/Al2O3 catalysts prepared by Pt and Sn coevaporation (solvated metal atom dispersion) ». Journal of Catalysis 126, no 1 (novembre 1990) : 173–86. http://dx.doi.org/10.1016/0021-9517(90)90055-o.

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Urumese, Ancila, Ramesh Naidu Jenjeti, S. Sampath et Balaji R. Jagirdar. « Colloidal europium nanoparticles via a solvated metal atom dispersion approach and their surface enhanced Raman scattering studies ». Journal of Colloid and Interface Science 476 (août 2016) : 177–83. http://dx.doi.org/10.1016/j.jcis.2016.05.015.

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León-Gutiérrez, Yasna, et Galo Cárdenas-Triviño. « Catalyst characterization Ni-Sn nanoparticles supported in Al2O3 and MgO : Acetophenone hydrogenation ». Nanomaterials and Nanotechnology 12 (janvier 2022) : 184798042211321. http://dx.doi.org/10.1177/18479804221132128.

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Monometallic and bimetallic Ni and Sn catalysts were prepared in different ratios by the Solvated Metal Atom Dispersed (SMAD) method for the catalytic hydrogenation of acetophenone to 1-phenylethanol. The preparation of the catalysts was carried out by evaporation of Ni and Sn metal atoms and subsequent co-deposition at 77 K using 2- isopropanol as solvent on alumina and magnesium oxide as supports. X-ray photoelectron spectroscopy (XPS) analysis showed a high percentage of nickel atoms in zero valence, while the tin phases were founded in reduced and oxidized form. The average size of the nanoparticles measured by transmission electron microscopy (TEM) ranged from 8 to 15 nm while the metal dispersion on the surface measured by hydrogen chemisorption ranged from 0.07% for Ni1% Sn0.3%/MgO to 3.2% for Ni5%/MgO. Thermogravimetric analysis shows that γ-Al2O3 catalysts exhibit higher thermal stability than MgO catalysts. The catalysis results showed that the best support is MgO reaching 66% conversion in Ni5% Sn0.5%/MgO catalyst.
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LI, Y. X., et K. J. KLABUNDE. « ChemInform Abstract : Studies of Pt-Sn/Al2O3 Catalysts Prepared by Pt and Sn Coevaporation ( Solvated Metal Atom Dispersion). » ChemInform 22, no 3 (23 août 2010) : no. http://dx.doi.org/10.1002/chin.199103028.

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Arora, Neha, et Balaji R. Jagirdar. « Monodispersity and stability : case of ultrafine aluminium nanoparticles (<5 nm) synthesized by the solvated metal atom dispersion approach ». Journal of Materials Chemistry 22, no 18 (2012) : 9058. http://dx.doi.org/10.1039/c2jm16764f.

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Akhmedov, Vagif, et Kenneth J. Klabunde. « High-activity Re—Pt/MO catalysts for C—C bond cleavage reactions : preparation by solvated metal atom dispersion (SMAD) ». Journal of Molecular Catalysis 45, no 2 (mai 1988) : 193–206. http://dx.doi.org/10.1016/0304-5102(88)80009-9.

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Cárdenas-Triviño, Galo, Macarena Ruiz-Parra, Luis Vergara-González, Javier Ojeda-Oyarzún et Guillermo Solorzano. « Synthesis and Bactericidal Properties of Hyaluronic Acid Doped with Metal Nanoparticles ». Journal of Nanomaterials 2017 (2017) : 1–9. http://dx.doi.org/10.1155/2017/9573869.

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A study on the nanoparticles size and the antibacterial properties of hyaluronic acid (HA) doped with nanoparticles is reported. Nanoparticles from gold, silver, copper, and silver palladium with HA support were performed. The solvated metal atom dispersion (SMAD) method with 2-propanol and HA was used. High-resolution transmission electron microscopy (HRTEM), infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA) were conducted. The average sizes of nanoclusters were as follows: HA-Au = 17.88 nm; HA-Ag = 50.41 nm; HA-Cu = 13.33 nm; and HA-AgPd = 33.22 nm. The antibacterial activity of solutions and films containing nanoparticles against American Type Culture Collection (ATCC) bacterial strainsEscherichia coli(EC),Staphylococcus aureus(SA),Staphylococcus epidermidis(SE), andPseudomonas aeruginosa(PA) was determined. Inhibition was observed for HA-Ag, HA-Cu, and HA-AgPd. Toxicological tests were performed in rats that were injected intraperitoneally with two concentrations of gold, copper, silver, and silver-palladium nanoparticles. No alterations in hepatic parameters, including ALT (alanine aminotransferase), GGT (gamma-glutamyl transpeptidase) bilirubin, and albumin, were observed after 14 days. These films could be used as promoters of skin recovery and Grades I and II cutaneous burns and as scaffolds.
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Bhattacharya, Chirasmita, et Balaji R. Jagirdar. « Monodisperse Colloidal Metal Nanoparticles to Core–Shell Structures and Alloy Nanosystems via Digestive Ripening in Conjunction with Solvated Metal Atom Dispersion : A Mechanistic Study ». Journal of Physical Chemistry C 122, no 19 (20 avril 2018) : 10559–74. http://dx.doi.org/10.1021/acs.jpcc.8b00874.

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Bhaskar, Srilakshmi P., Megha Vijayan et Balaji R. Jagirdar. « Size Modulation of Colloidal Au Nanoparticles via Digestive Ripening in Conjunction with a Solvated Metal Atom Dispersion Method : An Insight Into Mechanism ». Journal of Physical Chemistry C 118, no 31 (28 juillet 2014) : 18214–25. http://dx.doi.org/10.1021/jp505121b.

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Cárdenas-Triviño, Galo, María J. Saludes-Betanzo et Luis Vergara-González. « Bactericides Properties of Chitosan Metal Quantum Dots Microbial Pathogenicity Against E. coli, S. aureus, and S. Typhi ». International Journal of Polymer Science 2020 (25 septembre 2020) : 1–14. http://dx.doi.org/10.1155/2020/5920941.

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The nanotechnology is considered as a tool to overcome antibiotic-resistant infections. The aim of this study was to investigate the antibacterial properties of quantum dots (QDs) of Au, Ag, and Cu supported in chitosan against Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 29213), and Salmonella Typhi (ATCC 9993) strains. The QDs were synthesized by the method (Chemical Liquid Deposition, CLD) using 2-ethoxyethanol as solvent (1×10−3 M approximate dispersion concentration). Then, NPs supported in chitosan were synthesized by solvated metal atom dispersion (SMAD) in two concentrations, labelled [A] and [B] (0.05 and 0.1 g/L) for each metal with chitosan resulting in an average size of Au 10±2.0, Ag 6±1.3, and Cu 10±2.4 nm, respectively. Several other techniques were performed such as TEM, SEM/EDX, TGA, DSC, and FT-IR for characterizing QDs. The antibacterial assay was performed with 8 agents on cultures of E. coli, S. aureus, and S. Typhi by disk diffusion, broth macrodilution, and determining death curve to the most sensitive pathogen. The antibacterial effect of the nanoparticles was compared using the diameter of growth inhibition zone by agar disk diffusion and through the minimal inhibitory concentration (MIC) and minimal bactericide concentration (MBC) obtained by macrodilution in batch culture with an initial inoculum of 5×105 CFU/mL. The highest bactericidal effect was obtained with nanoparticles of Au, Ag, and Cu (0.1 g/L) with MIC and MBC of 200 and 400 mg/mL, respectively. The greatest bactericidal effect considering the three pathogens turned out to be Ag QDs (0.05 and 0.1 g/L). A bactericidal effect of metal nanoparticles is affected mainly by the electronegativity, the concentration of nanoparticles, and the bacterial age culture.
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Cingarapu, Sreeram, Zhiqiang Yang, Christopher M. Sorensen et Kenneth J. Klabunde. « Synthesis of CdSe/ZnS and CdTe/ZnS Quantum Dots : Refined Digestive Ripening ». Journal of Nanomaterials 2012 (2012) : 1–12. http://dx.doi.org/10.1155/2012/312087.

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We report synthesis of CdSe and CdTe quantum dots (QDs) from the bulk CdSe and CdTe material by evaporation/co-condensation using the solvated metal atom dispersion (SMAD) technique and refined digestive ripening. The outcomes of this new process are (1) the reduction of digestive ripening time by employing ligands (trioctylphosphine oxide (TOPO) and oleylamine (OA)) as capping agent as well as digestive ripening solvent, (2) ability to tune the photoluminescence (PL) from 410 nm to 670 nm, (3) demonstrate the ability of SMAD synthesis technique for other semiconductors (CdTe), (4) direct comparison of CdSe QDs growth with CdTe QDs growth based on digestive ripening times, and (5) enhanced PL quantum yield (QY) of CdSe QDs and CdTe QDs upon covering with a ZnS shell. Further, the merit of this synthesis is the use of bulk CdSe and CdTe as the starting materials, which avoids usage of toxic organometallic compounds, eliminates the hot injection procedure, and size selective precipitation processes. It also allows the possibility of scale up. These QDs were characterized by UV-vis, photoluminescence (PL), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and powder XRD.
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16

Shi-Hua, Wu, Zhao Wei-Jun, Yang Shu-Jun, Wang Xu-Kun, Zhang Shu-Ji et Fang Yan-Quan. « Preparation of Highly Dispersed Supported Metal Catalyst VIA Solvated Metal Atom Impregnation II. Dispersions and Catalytic Properties of Supported Fe,Co,Ni Catalysts ». Acta Physico-Chimica Sinica 7, no 05 (1991) : 543–48. http://dx.doi.org/10.3866/pku.whxb19910506.

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17

Stoeva, Savka, Kenneth J. Klabunde, Christopher M. Sorensen et Iovka Dragieva. « Gram-Scale Synthesis of Monodisperse Gold Colloids by the Solvated Metal Atom Dispersion Method and Digestive Ripening and Their Organization into Two- and Three-Dimensional Structures ». Journal of the American Chemical Society 124, no 10 (mars 2002) : 2305–11. http://dx.doi.org/10.1021/ja012076g.

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Klabunde, Kenneth J., Yong Xi Li et Beng Jit Tan. « Solvated metal atom dispersed catalysts ». Chemistry of Materials 3, no 1 (janvier 1991) : 30–39. http://dx.doi.org/10.1021/cm00013a013.

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19

Li, Zeng Xin, Tong Zhu Han, Wen Xia Guo et Guo Ming Wang. « The Comparison of Different Preparation Methods of Catalysts for Furfural Hydrogenization to 2 - Methyl Furan ». Advanced Materials Research 791-793 (septembre 2013) : 68–71. http://dx.doi.org/10.4028/www.scientific.net/amr.791-793.68.

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Three different kinds of preparation methods were contrasted and studied to furfural hydrogenation catalyst for 2 - methyl furan production.Cu, Cr-based catalysts are prepared by three different methods, and the differences were also studied in the structure of these catalysts and their catalytic properties on furfural hydrogenation reaction. From the XRD patterns of samples prepared by different methods of Cu-Cr/γ-Al2O3, The results show that: the metal particle size is:the ordinary impregnation method > coprecipitation > solvated metal atom impregnation method. From the SEM photographs by samples, distribution uniformity of the catalyst ion surface: ordinary impregnation method > coprecipitation > solvated metal atom impregnation method. The reduction degree of the metal: solvated metal atom impregnation ordinary impregnation coprecipitation method. Furfural hydrogenation experimental results show that the order of catalytic activity is solvated metal atom > general impregnation coprecipitation; the selectivity order of 2 - methyl furan: coprecipitation> ordinary impregnation method solvated metal atom impregnation method.
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20

KLABUNDE, K. J., Y. X. LI et B. J. TAN. « ChemInform Abstract : Solvated Metal Atom Dispersed Catalysts ». ChemInform 22, no 15 (23 août 2010) : no. http://dx.doi.org/10.1002/chin.199115310.

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21

Kanai, Hiroyoshi, Beng Jit Tan et Kenneth J. Klabunde. « Fischer-Tropsch reactions over mono- and bimetallic solvated metal atom dispersed catalysts ». Langmuir 2, no 6 (novembre 1986) : 760–65. http://dx.doi.org/10.1021/la00072a015.

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22

MEIER, P. « Iron and cobalt Fischer-Tropsch catalysts prepared by the solvated metal-atom technique ». Journal of Catalysis 101, no 2 (octobre 1986) : 545–48. http://dx.doi.org/10.1016/0021-9517(86)90285-x.

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23

Klabunde, Kenneth, et Yuzo Imizu. « Correction. Bimetallic Solvated Metal Atom Dispersed Catalysts. New Materials with Low-Temperature Catalytic Properties ». Journal of the American Chemical Society 107, no 26 (décembre 1985) : 8310. http://dx.doi.org/10.1021/ja00312a602.

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Tan, Beng Jit, Kenneth J. Klabunde, Tsunehiro Tanaka, Hiroyoshi Kanai et Satohiro Yoshida. « An EXAFS study of cobalt-manganese/silica bimetallic solvated metal atom dispersed (SMAD) catalysts ». Journal of the American Chemical Society 110, no 18 (août 1988) : 5951–58. http://dx.doi.org/10.1021/ja00226a004.

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Chen, Taoyi, et Thomas A. Manz. « A collection of forcefield precursors for metal–organic frameworks ». RSC Advances 9, no 63 (2019) : 36492–507. http://dx.doi.org/10.1039/c9ra07327b.

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Atom-in-material (AIM) partial charges, dipoles and quadrupoles, dispersion coefficients (C6, C8, C10), polarizabilities, electron cloud parameters, radial moments, and atom types were extracted from quantum chemistry calculations for >3000 MOFs.
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Zhang, Tao. « Single-Atom Catalysis : Far beyond the Matter of Metal Dispersion ». Nano Letters 21, no 23 (22 novembre 2021) : 9835–37. http://dx.doi.org/10.1021/acs.nanolett.1c02681.

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Wu, Shi-Hua, Xiu-Cheng Zheng, Shu-Rong Wang, Dong-Zhan Han, Wei-Ping Huang et Shou-Min Zhang. « TiO2Supported Nano-Au Catalysts Prepared Via Solvated Metal Atom Impregnation for Low–Temperature CO Oxidation ». Catalysis Letters 96, no 1/2 (juillet 2004) : 49–55. http://dx.doi.org/10.1023/b:catl.0000029528.60669.cf.

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Wu, Shi-Hua, Xiu-Cheng Zheng, Shu-Rong Wang, Dong-Zhan Han, Wei-Ping Huang et Shou-Min Zhang. « TiO2Supported Nano—Au Catalysts Prepared via Solvated Metal Atom Impregnation for Low-Temperature CO Oxidation ». Catalysis Letters 97, no 1/2 (août 2004) : 17–23. http://dx.doi.org/10.1023/b:catl.0000034279.03771.c2.

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Sethia, Ashok, Eric R. Bittner et Fumio Hirata. « Interplay Between the Repulsive and Attractive Interaction and the Spacial Dimensionality of an Excess Electron in a Simple Fluid ». Journal of Theoretical and Computational Chemistry 02, no 02 (juin 2003) : 129–38. http://dx.doi.org/10.1142/s0219633603000495.

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The behavior of an excess electron in a one, two and three dimensional classical liquid has been studied with the aid of Chandler, Singh and Richardson (CSR) theory [J. Chem. Phys.81, 1975 (1984)]. The size or dispersion of the wavepacket associated with the solvated electron is very sensitive to the interaction between the electron and fluid atoms, and exhibits complicated behavior in its density dependence. The behavior is interpreted in terms of an interplay among four causes: the excluded volume effect due to solvent, the pair attractive interaction between the electron and a solvent atom, the thermal wavelength of the electron (λe), a balance of the attractive interactions from different solvent atoms and the range of repulsive interaction between electron and solvent atom. Electron self-trapping behavior in all the dimensions has been studied for the same solvent-solvent and electron-solvent interaction potential and the results are presented for the same parameter in every dimension to show the comparison between the various dimensions.
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CARDENAS, G. « Synthesis and properties of PdSn/Al2O3 and PdSn/SiO2 prepared by solvated metal atom dispersed method ». Journal of Molecular Catalysis A : Chemical 191, no 1 (janvier 2003) : 75–86. http://dx.doi.org/10.1016/s1381-1169(02)00333-3.

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Hernández-Calva, Adriana, Lidia Meléndez-Balbuena, Maribel Arroyo et Armando Ramírez-Monroy. « Crystal structure of azido(η5-cyclopentadienyl)bis(triphenylphosphane-κP)ruthenium(II) dichloromethane hemisolvate ». Acta Crystallographica Section E Structure Reports Online 70, no 10 (6 septembre 2014) : m345—m346. http://dx.doi.org/10.1107/s1600536814019187.

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The title solvated complex, [Ru(η5-C5H5)(N3){P(C6H5)3}2]·0.5CH2Cl2, displays a typical piano-stool geometry about the RuIIatom. The bond lengths and angles of the cyclopentadienyl and phosphane ligands are very similar to that of the unsolvated complex [Taqui Khanet al.(1994).Acta Cryst.C50, 502–504]. The azide anion displays similar N—N distances of 1.173 (3) and 1.156 (3) Å and has an N—N—Ru angle of 119.20 (15)°, indicating a greater contribution of the canonical form Ru—N=N(+)=N(-)for the bonding situation. An intramolecular C—H...N hydrogen-bonding interaction between oneorthoH atom of a phosphane ligand and the N atom coordinating to the metal is observed. A similar intermolecular interaction is observed between ametaH atom of a phosphane ligand and the terminal azide N atom of a neighbouring complex. Finally, two C—H...N interactions exists between the H atoms of the dichloromethane solvent molecule and the terminal N atom of two azide anions. The solvent molecule is located about a twofold rotation axis and shows disorder of the Cl atoms with an occupancy ratio of 0.62 (3):0.38 (3).
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Ishiguro, Shin-ichi, Yasuhiro Umebayashi, Kenta Fujii et Ryo Kanzaki. « Solvent conformation and ion solvation : From molecular to ionic liquids ». Pure and Applied Chemistry 78, no 8 (1 janvier 2006) : 1595–609. http://dx.doi.org/10.1351/pac200678081595.

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Metal ions are solvated in solution, and, in a sterically congested organic solvent, those solvent molecules that are simultaneously bound to the metal ion will be subject to consequential steric interactions through space. The molecular structure of a solvent, particularly that of any functional groups in the vicinity of the coordinating atom to the metal ion, plays a key role in the solvation steric effect. Weak solvation steric effects lead to a distorted octahedral structure for six-coordinate transition-metal(II) ions, whereas strong steric effects lead to a decreased solvation number. In particular cases, the conformation of a solvent may undergo a change in response to coordination to the metal ion. Solvation steric effects play a decisive role in reaction thermodynamics and kinetics of the metal ion. Here, we show our recent results on solvation steric effects in terms of structure and thermodynamics, particularly, the conformational change of solvent and its effect on the metal-ion complexation.
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Khalili, Behzad, et Mehdi Rimaz. « Interaction of l-proline with group IIB (Zn2+, Cd2+, Hg2+) metal cations in the gas and aqueous phases : a quantum computational study ». Canadian Journal of Chemistry 94, no 5 (mai 2016) : 501–8. http://dx.doi.org/10.1139/cjc-2015-0616.

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The gas and aqueous phase complexation geometries, electronic interactions, and metal ion affinities of Zn2+, Cd2+, and Hg2+ metal cations with the two most stable conformations of l-proline complexes were studied. The complexes were optimized by density functional theory (B3LYP) using the 6-311++G(d,p) orbital basis set and relativistic pseudopotentials for the metal cations. The interactions of the metal cations at different nucleophilic sites of l-proline were considered as were three modes of interactions including salt bridged, charge solvated 1, and charge solvated 2, which are indicative of binding in a bidentate manner through the carboxylate group, carbonyl and hydroxyl oxygen, and carbonyl oxygen and the nitrogen atom of l-proline. All of the coordination patterns were characterized by both charge transfer and ionic interactions between l-proline and the metal cation. The metal ion affinity (MIA) and interaction energy were also computed for all of the complexes at both the gas and aqueous phases. Results showed that the order of MIA at the gas and aqueous phases are different. MIA order at the gas phase was in the order of Zn2+ > Hg2+ > Cd2+ whereas at the aqueous phase, the order of Zn2+ > Cd2+ > Hg2+ was obtained for MIA. The infrared stretching vibrational modes of the N–H and O–H groups of free l-proline were compared with l-proline–M2+ in both CS1 and CS2 coordination patterns at the gas phase and results showed a considerable shift to lower frequency during complexation process.
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Hori, Akiko, Kyosuke Nakajima et Hidetaka Yuge. « Threep-xylene-solvated pseudopolymorphs of bis[1,3-bis(pentafluorophenyl)propane-1,3-dionato]copper(II) ». Acta Crystallographica Section C Structural Chemistry 70, no 10 (28 septembre 2014) : 960–64. http://dx.doi.org/10.1107/s2053229614020294.

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The Cu2+ions in the title compounds, namely bis[1,3-bis(pentafluorophenyl)propane-1,3-dionato-κ2O,O′]copper(II)p-xylenen-solvate, [Cu(C15HF10O2)2]·nC8H10, withn= 1, (I),n = 2, (II), andn= 4, (III), are coordinated by two 1,3-bis(pentafluorophenyl)propane-1,3-dionate ligands. The coordination complexes of (I) and (II) have crystallographic inversion symmetry at the Cu atom and thep-xylene molecule in (I) also lies across an inversion centre. Thep-xylene molecules in (I) and (II) interact with the pentafluorophenyl groups of the complexviaarene–perfluoroarene interactions. In the crystal of (III), two of thep-xylene molecules interact with the pentafluorophenyl groupsviaarene–perfluoroarene interactions. The other twop-xylene molecules are located on the CuO4coordination plane, forming a uniform cavity produced by metal...π interactions.
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Yu, Li-hua, Shou-min Zhang, Xianzhi Guo, Da Wang, Shu-rong Wang et Shi-hua Wu. « Influence of the addition of Pd and Cu to cobalt catalysts prepared by SMAI for F-T synthesis ». Open Chemistry 5, no 1 (1 mars 2007) : 144–55. http://dx.doi.org/10.2478/s11532-006-0062-9.

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AbstractThe Co-Pd/SiO2 and Co-Cu/SiO2 catalysts were prepared via solvated metal atom impregnation (SMAI) method and investigated for the Fischer-Tropsch (F-T) synthesis. The catalysts contained 5wt.% Co and a weight ratio of Pd (or Cu) to Co of 1/30. XPS indicated that Co, Pd and Cu were in metallic state. The results of XPS and magnetic measurements showed that Co and Pd (Cu) were alloyed. The Co particles on the catalysts were very highly dispersed and they displayed superparamagnetic behavior. FT-IR indicated that the electrons shifted from Cu and Pd to Co. Catalytic tests showed that CO hydrogenation rates followed the order Pd-Co &gt; Cu-Co &gt; Co.
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Liebing, Phil, Ahmad Zaeni, Falk Olbrich et Frank T. Edelmann. « Crystal structures of two solvates of (18-crown-6)potassium acetate ». Acta Crystallographica Section E Crystallographic Communications 72, no 12 (8 novembre 2016) : 1757–61. http://dx.doi.org/10.1107/s2056989016017436.

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The crystal and molecular strutures of two solvated forms of [K(18c6)]OAc (18c6 = 18-crown-6 = 1,4,7,10,13,16-hexaoxacyclooctadecane and OAc = acetate) were determined by single-crystal X-ray diffraction, namely (acetato-κ2O,O′)(1,4,7,10,13,16-hexaoxacyclooctadecane-κ6O)potassium dihydrate, [K(CH3COO)(C12H24O6)]·2H2O (1) and (acetato-κ2O,O′)aqua(1,4,7,10,13,16-hexaoxacyclooctadecane-κ6O)potassium acetic acid monosolvate [K(CH3COO)(C12H24O6)(H2O)]·CH3COOH (2). In both compounds, the acetate anion is bonded to the potassium ion in a chelating fashion and the metal atom is consequently slightly displaced from the O6plane of the crown ether. In the crystals, O—H...O hydrogen bonds lead to a polymeric ladder structure in the dihydrate1, while the acetic acid hydrate2features inversion dimers.
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37

Jang, Myeong Gon, Sinmyung Yoon, Dongjae Shin, Hyung Jun Kim, Rui Huang, Euiseob Yang, Jihun Kim, Kug-Seung Lee, Kwangjin An et Jeong Woo Han. « Boosting Support Reducibility and Metal Dispersion by Exposed Surface Atom Control for Highly Active Supported Metal Catalysts ». ACS Catalysis 12, no 8 (30 mars 2022) : 4402–14. http://dx.doi.org/10.1021/acscatal.2c00476.

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Lu, Zhansheng, Peng Lv, Jie Xue, Huanhuan Wang, Yizhe Wang, Yue Huang, Chaozheng He, Dongwei Ma et Zongxian Yang. « Pd1/BN as a promising single atom catalyst of CO oxidation : a dispersion-corrected density functional theory study ». RSC Advances 5, no 103 (2015) : 84381–88. http://dx.doi.org/10.1039/c5ra14057a.

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Single metal atom catalysts exhibit extraordinary activity in a large number of reactions, and some two-dimensional materials (such as graphene and h-BN) are found to be prominent supports to stabilize single metal atoms.
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39

Tan, Beng Jit, Kenneth J. Klabunde et Peter M. A. Sherwood. « XPS studies of solvated metal atom dispersed (SMAD) catalysts. Evidence for layered cobalt-manganese particles on alumina and silica ». Journal of the American Chemical Society 113, no 3 (janvier 1991) : 855–61. http://dx.doi.org/10.1021/ja00003a019.

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Yu, Lihua, Xiaoxiang Zhang, Zongjie Du, Da Wang, Shurong Wang et Shihua Wu. « Preparation of Nano-Sized γ-Al2O3 Supported Iron Catalyst for Fischer-Tropsch Synthesis by Solvated Metal Atom Impregnation Methods ». Journal of Natural Gas Chemistry 16, no 1 (mars 2007) : 46–52. http://dx.doi.org/10.1016/s1003-9953(07)60025-5.

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41

Dennehy, Mariana, Ricardo M. Ferullo, Eleonora Freire et Ricardo Baggio. « An ethanol-solvated centrosymmetric dimer of bismuth(III) and thiosaccharinate resulting from `semicoordination' contacts ». Acta Crystallographica Section C Structural Chemistry 70, no 6 (28 mai 2014) : 627–31. http://dx.doi.org/10.1107/s2053229614010869.

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In the title compound, bis(μ-1,1-dioxo-1,2-benzothiazole-3-thiolato)-κ3N,S:S;κ3S:N,S-bis[(1,1-dioxo-1,2-benzothiazole-3-thiolato-κ2N,S)(ethanol-κO)bismuth(III)] ethanol hemisolvate, [Bi2(C7H4NO2S2)6(C2H5OH)2]·0.5C2H5OH, three independent thiosaccharinate (tsac) anions chelate the metal centre through the endocyclic N and exocyclic S atoms. The complex also presnts two `semicoordination' contacts, one from a pendant ethanol solvent molecule and a second one from an S atom of a centrosymmetrically related molecule. This latter interaction complements two π–π interactions between tsac rings to form a dimeric entity which is the elemental unit that builds up the crystal structure. These dinuclear units are connected to each otherviaa second type of π–π interaction, generating chains along [1\overline{1}1]. Two ethanol molecules, one of them of full occupancy at a general position and semicoordinated to the central cation, and a second one depleted and disordered around a symmetry centre, stabilize the structure. The complex was studied theoretically and the vibrational assignations were confirmed by employing theoretical density functional theory (DFT) methods.
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42

Ganesan, M., et S. Paranthaman. « Dispersion-corrected density functional theory studies on glycolic acid-metal complexes ». Журнал структурной химии 62, no 8 (2021) : 1251–69. http://dx.doi.org/10.26902/jsc_id78515.

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The structure and metal complexation studies using dispersion-corrected density functional theory methods are performed for four stable glycolic acid conformers named SSC, GAC, SAC, and AAT. The condensed Fukui functions are calculated to study the favourable reactive site for metal binding on the glycolic acid conformers. The interaction of alkali metal ions (Na+, K+) with different binding sites (carboxyl, hydroxyl oxygen) of the glycolic acid conformers in the gas phase is investigated at the same level of theory. Our calculations show that the order of stability changes into SSC > AAT > GAC = SAC due to the binding of the metal ion. The relative energy values indicate that the AAT conformer is more stable than the GAC and SAC conformers. This occurs when a metal ion (Na+, K+) is bound with the carboxyl oxygen atom of glycolic acid. The QTAIM, RDG, NCI, ELF, LOL, and NBO analysis are employed in this work to understand the strength of intra- and intermolecular interactions in the glycolic acid metal complexes.
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Wang, Dong, Xin Wang, Yue Lu, Changsheng Song, Jie Pan, Chilin Li, Manling Sui, Wei Zhao et Fuqiang Huang. « Atom-scale dispersed palladium in a conductive Pd0.1TaS2 lattice with a unique electronic structure for efficient hydrogen evolution ». Journal of Materials Chemistry A 5, no 43 (2017) : 22618–24. http://dx.doi.org/10.1039/c7ta06447k.

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Tan, Beng Jit, Kenneth J. Klabunde et Peter M. A. Sherwood. « X-ray photoelectron spectroscopy studies of solvated metal atom dispersed catalysts. Monometallic iron and bimetallic iron-cobalt particles on alumina ». Chemistry of Materials 2, no 2 (mars 1990) : 186–91. http://dx.doi.org/10.1021/cm00008a021.

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45

Yan, Qiangu, et Zhiyong Cai. « Effect of Solvents on Fe–Lignin Precursors for Production Graphene-Based Nanostructures ». Molecules 25, no 9 (6 mai 2020) : 2167. http://dx.doi.org/10.3390/molecules25092167.

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Kraft lignin was catalytically graphitized to graphene-based nanostructures at high temperature under non-oxidative atmospheres. To obtain the best catalytic performance, a uniform catalyst–lignin mixture must be made by bonding transitional metal (M) ions to oxygen (O), sulfur (S) or nitrogen (N)-containing functional groups in kraft lignin. One of the strategies is to dissolve or disperse kraft lignin in a suitable solvent, whereby the polymer chains in the condensed lignin molecules will be detangled and stretched out while the functional groups are solvated, and when mixing lignin solution with catalyst metal solution, the solvated metal ions in an aqueous solution can diffuse and migrate onto lignin chains to form M-O, M-S, or M-N bonds during the mixing process. Therefore, solvent effects are important in preparing M–lignin mixture for production of graphene-based nanostructures. Fe–lignin precursors were prepared by dissolving lignin with different solvents, including water, methanol, acetone, and tetrahydrofuran (THF). Solvent effects on the catalytic performance, size and morphology of graphene-based nanostructures were investigated using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HRTEM), and nitrogen sorption measurements. The sizes, morphologies, and catalytic properties of the products obtained from Fe–lignin precursors are greatly influenced by the solvents used. It was found that Fe–lignin (THF) had the highest iron dispersion and the smallest iron particle size. Furthermore, Fe–lignin (THF) exhibited the best catalytic performance for graphitization of kraft lignin while the graphitization degree decreased in the order: Fe–lignin(THF) > Fe–lignin(Acetone) > Fe–lignin(methanol) > Fe–lignin(water).
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46

Aggarwal, Amit, Sunaina Singh et Charles M. Drain. « Nanoaggregates of Mn(III)tetraperfluorophenylporphyrin : a greener approach for allylic oxidation of olefins ». Journal of Porphyrins and Phthalocyanines 15, no 11n12 (novembre 2011) : 1258–64. http://dx.doi.org/10.1142/s1088424611004130.

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Organic nanoparticles of metalloporphyrins can be a versatile catalyst for the selective oxidation of alkenes and other hydrocarbons. The catalytic activity of the metalloporphyrin depends on the nature of the central metal atom, peripheral groups, and the architecture of the porphyrin macrocycle. Herein, we report the catalytic activity of organic nanoparticles of 5,10,15,20-tetrakis-(2,3,4,5,6-pentafluorophenyl)porphyrinato manganese(III), Mn (III)TPPF20, for the oxidation of cyclohexene using molecular oxygen as an oxidant in aqueous solvent under ambient conditions. While the solvated metalloporphyrins catalytically oxidize alkenes to the corresponding epoxide with a modest turn-over numbers, ca. 30 nm organic nanoparticles of Mn (III)TPPF20 have enhanced catalytic activity with up to a two-fold greater turn-over number and yields only allylic oxidation products. The activity of organic nanoparticles is slow compared to the solvated metalloporphyrins. These organic nanoparticles catalytic systems facilitate a greener reaction since ca. 89% of the reaction medium is water, molecular oxygen is used in place of man-made oxidants, and the ambient reaction conditions require less energy. This organic nanoparticle catalytic system also avoids using halogenated solvents commonly used in solution phase reactions. The enhanced catalytic activity of these organic nanoparticles is unexpected because the metalloporphyrins in the nanoaggregates are in the close proximity and the turn-over number should diminish by self-oxidative degradation.
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Misaizu, Fuminori, Keizo Tsukamato, Masaomi Sanekata et Kiyokazu Fuke. « Photoelectron Spectroscopy of Mass-Selected Copper-Water Cluster Negative Ions ». Laser Chemistry 15, no 2-4 (1 janvier 1995) : 195–207. http://dx.doi.org/10.1155/1995/68042.

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Negative-ion photoelectron spectroscopy has been applied in order to obtain size dependent information about the electronic structure of clusters of metal atoms solvated with polar molecules. In the present paper we have investigated the photoelectron spectra of Cu2-(H2O)n, cluster ions with 2 = 0–4 and also those of Cu2-(H2O)n, with n = 0 and 1. In the spectra of Cu2-(H2O)n, the lowest energy bands were assigned to the electron detachment from the CuOH-(H2O)n−1, which were produced in the source together with the above cluster ions. The observed bands for Cu2-(H2O)n were all assigned to the transitions to the states originating in the ground 2S and first excited 2D states of the Cu atom. The stepwise hydration for Cu- and Cu2- was discussed from the observed spectral shifts.
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48

Jeong, Hojin, Ohmin Kwon, Beom-Sik Kim, Junemin Bae, Sangyong Shin, Hee-Eun Kim, Jihan Kim et Hyunjoo Lee. « Highly durable metal ensemble catalysts with full dispersion for automotive applications beyond single-atom catalysts ». Nature Catalysis 3, no 4 (17 février 2020) : 368–75. http://dx.doi.org/10.1038/s41929-020-0427-z.

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49

Engelhardt, LM, PC Healy, JD Kildea et AH White. « Lewis-Base Adducts of Group 11 Metal(I) Compounds. LI. Synthesis and Structural Characterization of Mononuclear Chloro-, Bromo- and Iodo-pyridinebis(triphenylphosphine)copper(I) Complexes ». Australian Journal of Chemistry 42, no 6 (1989) : 895. http://dx.doi.org/10.1071/ch9890895.

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Complexes [ XCu ( py )(PPh3)2], X = Cl, Br, I, py = pyridine, have been synthesized and characterized by single-crystal X-ray structure determination. Chloride and iodide derivatives have similar cells [ isomorphous (?) but not isostructural ], triclinic, pi, a = 19.5 A, b = 10.5, c = 9.6 � , α ≈ 66, β ≈ 86, γ ≈ 83�, Z = 2; the bromide is monoclinic, Cc, a 13.568(9), b 15.760(12), c 16.545(8) � , β 95.65(5)�, Z = 4. Cl, Br, I structures were refined to residuals of 0.042, 0.055, 0.039 for 4288, 2241, 4808 'observed' reflections. In all cases, the copper atom is four-coordinate; for such an array, Cu-X lengths are unusually short [2.318(2), 2.459(2), 2.636(1) � (Cl, Br, I) and Cu-N unusually long (2.14(1) � ], while (Cu-P) increase from 2.264 to 2.288 � across the series. The dominant aspect of the complexes is thus that of XCu (PPh3)2 solvated by pyridine.
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Shen, Xing, et Kairui Liu. « Discrete Au1(0) Stabilized by 15-Crown-5 for High-Efficiency Catalytic Reduction of Nitrophenol and Nitroaniline ». Catalysts 13, no 4 (20 avril 2023) : 776. http://dx.doi.org/10.3390/catal13040776.

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Single-atom catalysts (SACs) have been synthesized using a variety of methods in recent years, and they have shown excellent catalytic activities. However, metal atoms show a high tendency to agglomerate in liquid media, making the single atom synthesis more difficult in liquid media. The synthesis of such metal single-atom catalysts that do not have strong ligand coordination is rarely reported in the literature. Herein, we report the facile synthesis of monodispersed Au atoms (Au1) through the reduction in HAuCl4 in 15-crown-5. The complete reduction in HAuCl4 was confirmed through UV-Vis spectroscopy. In addition, the Au was found in a zero valence state after reduction, which was confirmed through XPS and XANES results. Moreover, the dispersion of Au was confirmed as a single atom (Au1) through transmission electron microscopy and spherical aberration electron microscopy. The possible structure of this catalyst was proposed by matching the EXAFS results with the structure of Au1@15-crown-5 as -(OC2H4O)-AuCl2H2. The Au1@15-crown-5 showed high activity (TOF as high as 22,075) in the reduction in nitrophenol and nitroaniline to aminophenol and phenylenediamine by sodium borohydride. Because of the monodispersion of Au atoms, its performance is much better than noble nanoparticles and non-precious metal catalysts.
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