Spectrophotometric and voltammetric characterization of complexes of bis(2,2'-bipyridine)(2,2'-bibenzimidazole)ruthenium and -osmium in oxidation states II, III, and IV in acetonitrile/water mixtures

1986 ◽  
Vol 25 (25) ◽  
pp. 4507-4514 ◽  
Author(s):  
Alan M. Bond ◽  
Masaaki Haga
Keyword(s):  
Oxidation States

Catalytic Fluorination of Boron Compounds at a Bismuth Redox Platform

2019 ◽  
Author(s):  
Oriol Planas ◽  
Feng Wang ◽  
Markus Leutzsch ◽  
Josep Cornella
Keyword(s):  
Transition Metal ◽  
Main Group ◽  
Group Element ◽  
Oxidation States ◽  
Boron Compounds ◽  
Main Text ◽  
Main Group Element ◽  
Rational Ligand Design ◽  
Supplementary Material

The ability of bismuth to maneuver between different oxidation states in a catalytic redox cycle, mimicking the canonical organometallic steps associated to a transition metal, is an elusive and unprecedented approach in the field of homogeneous catalysis. Herein we present a catalytic protocol based on bismuth, a benign and sustainable main-group element, capable of performing every organometallic step in the context of oxidative fluorination of boron compounds; a territory reserved to transition metals. A rational ligand design featuring hypervalent coordination together with a mechanistic understanding of the fundamental steps, permitted a catalytic fluorination protocol based on a Bi(III)/Bi(V) redox couple, which represents a unique example where a main-group element is capable of outperforming its transition metal counterparts.<br>A main text and supplementary material have been attached as pdf files containing all the methodology, techniques and characterization of the compounds reported.<br>

Electrochemistry of nickel picket fence porphyrin. Electrogeneration and spectral characterization of nickel complexes in unusual oxidation states

1989 ◽  
Vol 28 (13) ◽  
pp. 2542-2547 ◽  
Author(s):  
K. M. Kadish ◽  
D. Sazou ◽  
G. B. Maiya ◽  
B. C. Han ◽  
Y. M. Liu ◽  
...  
Keyword(s):  
Nickel Complexes ◽  
Spectral Characterization ◽  
Oxidation States ◽  
Picket Fence

Characterization of Intermediate Oxidation States in CO2Activation

2018 ◽  
Vol 69 (1) ◽  
pp. 231-252 ◽  
Author(s):  
Leah G. Dodson ◽  
Michael C. Thompson ◽  
J. Mathias Weber
Keyword(s):  
Oxidation States ◽  
Intermediate Oxidation

scholarly journals Synthesis and Characterization of New Homo- and Heteronuclear Schiff Base Complexes

Proceedings ◽  
2019 ◽  
Vol 29 (1) ◽  
pp. 77
Author(s):  
Spinciu ◽  
Maxim ◽  
Pătrașcu ◽  
Popescu
Keyword(s):  
Schiff Base ◽  
Schiff Bases ◽  
Chemical Elements ◽  
Schiff Base Complexes ◽  
Oxidation States ◽  
Synthesis And Characterization

Schiff bases are the most extensively used versatile ligands, capable of coordinating several chemical elements and stabilizing them in numerous oxidation states. [...]

Characterization of the Oxidation States of Supported Gold Species by IR Spectroscopy of Adsorbed CO

2007 ◽  
Vol 79 (6) ◽  
pp. 795-806 ◽  
Author(s):  
M. Mihaylov ◽  
H. Knözinger ◽  
K. Hadjiivanov ◽  
B. C. Gates
Keyword(s):  
Ir Spectroscopy ◽  
Oxidation States ◽  
Adsorbed Co ◽  
Supported Gold

Characterization of Copper-Ceramic Interfaces

1984 ◽  
Vol 40 ◽  
Author(s):  
W. M. Kriven ◽  
S. H. Risbud
Keyword(s):  
Electron Probe ◽  
Interfacial Microstructure ◽  
Oxidation States ◽  
Thermodynamics And Kinetics ◽  
Specific Goal ◽  
Reaction Zones ◽  
Ceramic Interfaces ◽  
Kinetics Of ◽  
Oxidation State Of Copper

AbstractThe interfacial zones in copper-magnesium aluminosilicate materials were characterized by several microscopic and microchemical techniques. Interfaces between copper-glass, copper-partially crystallized glass, and copper-fully crystallized glass were studied with the specific goal of determining the oxidation state of copper in various locations in the microstructure of the reaction zones. Optical microscopy, cathodoluminescence, electron probe microanalysis (EPMA), SEM, TEM, and other microtechniques were used. The presence of copper in various oxidation states can be attributed to the thermodynamics and kinetics of the system. Results correlating the observed interfacial microstructure and the thermochemistry of the system are presented.

Characterization of europium implanted LiNbO3

1993 ◽  
Vol 8 (10) ◽  
pp. 2679-2685 ◽  
Author(s):  
P. Moretti ◽  
B. Canut ◽  
S.M.M. Ramos ◽  
R. Brenier ◽  
P. Thévenard ◽  
...  
Keyword(s):  
Single Crystals ◽  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Rutherford Backscattering ◽  
Oxidation States ◽  
Xps Spectra ◽  
X Ray ◽  
Partial Recrystallization ◽  
Lower Charge

LiNbO3 single crystals were implanted at room temperature with Eu+ ions at 70 keV with fluence ranging from 0.5 to 5 × 1016 ions · cm−2. The damage in the implanted layer has been investigated by Channeling Rutherford Backscattering (RBS-C), and the oxidation states of the cations have been determined by x-ray photoelectron spectroscopy (XPS). Following implantation, a fully amorphized layer of 60 nm is generated, even for the lowest fluence employed. Subsequent annealing in air, in the range 800–1250 K, was applied to restore tentatively the crystallinity and promote the substitutional incorporation of Eu in the crystal. Only a partial recrystallization of the damaged layer was observed. For as-implanted samples, XPS spectra clearly reveal europium in Eu2+ and Eu3+ states, and the Nb5+ ions are driven to lower charge states.

Characterization of Th Carbonate Solutions Using XAS and Implications for Thermodynamic Modeling

1996 ◽  
Vol 465 ◽  
Author(s):  
N. J. Hess ◽  
A. R. Felmy ◽  
D. Rai ◽  
S. D. Conradson
Keyword(s):  
Chemical Speciation ◽  
Chelating Agents ◽  
Chemical Species ◽  
Oxidation States ◽  
Carbonate Solutions ◽  
Ph Conditions ◽  
High Concentrations ◽  
Aqueous Complexes ◽  
Aqueous Species

ABSTRACTThe chemical behavior of actinide elements in tank solutions, in soil, and in groundwater is dependent upon the chemical species that form when aqueous solutions come in contact with the actinide compounds. In particular the chemical speciation of the reduced actinide oxidation states (III and IV) are important, for example, to DOE waste tank processing and, more generally, to nuclear waste disposal issues. Predicting the solubility of the actinides in these solutions requires identification of the strong aqueous complexes, such as carbonates and organic chelating agents, that can form in aqueous solution.Previous speciation work has often relied on indirect techniques such as potentiometric titrations or solubility measurements. Recent XAS experiments determine directly the speciation of the Th carbonato species of seven solutions under a range of carbonate concentrations and pH conditions. The presence of the pentacarbonato complex is confirmed and the complex's stability at low carbonate concentrations is determined. These experimental results support a proposed thermodynamic model that describes the solubility of Th(IV) hydrous oxide in the aqueous Na+-HCO3--CO32--OH--ClO4--H2O system extending to high concentrations at 25°C. This model is relatively simple in that only two aqueous species are included Th(OH)3CO3- and Th(CO3)56-.

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