Chemical kinetics of nickel(III) macrocyclic complexes. Pulse radiolysis study of Ni/sup II/(CR+4H), Ni/sup II/(CR), and Ni/sup II/(CR-2H) in aqueous solutions of Br/sup -/ and CNS/sup -/. [Gamma radiation]
Journal Article
·
· Inorg. Chem.; (United States)
Oxidation of three closely related nickel (II) macrocyclic complexes Ni/sup II/(CR-2H), Ni/sup II/(CR), and Ni/sup II/(CR+4H) via anion radical reaction has been investigated by pulse radiolysis methods. While the initial oxidation products follow the form Ni/sup III/(L)(X/sup -/)(H/sub 2/O), in agreement with previous studies (L = macrocyclic ligand; X/sup -/ = Br/sup -/, SCN/sup -/), pH- and anion-concentration-dependent behavior provides evidence indicating subsequent formation of several other complexes Ni/sup III/(L)(X/sup -/)/sub 2/, Ni/sup III/(L)(OH/sup -/)(H/sub 2/O), Ni/sup III/(L)(OH/sup -/), and Ni/sup III/(L)(OH/sup -/)/sub 2/. The kinetics for interconversion among these species have been measured and are found in several cases to exhibit reversible behavior. In those cases the associated equilibrium constants have been determined. The formation of Ni/sup III/(L)(X/sup -/)/sub 2/ may be seen to depend on the degree of macrocyclic unsaturation and character of the anion. With the exception of the fully unsaturated CR-2H ligand, Ni/sup III/(L)(OH/sup -/) and Ni/sup III/(L)(OH/sup -/)(H/sub 2/O) and Ni/sup III/(L)(OH/sup -/)/sub 2/ decay via ligand radical formation at neutral pH and higher. Steady-state radiolysis results indicate introduction of an additional double bond into the ligand. At low pH, anion-substituted Ni(III) species return almost quantitatively to their parent Ni(II) complexes.
- Research Organization:
- Univ. of Notre Dame, IN
- OSTI ID:
- 5192778
- Journal Information:
- Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Vol. 21:5; ISSN INOCA
- Country of Publication:
- United States
- Language:
- English
Similar Records
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Journal Article
·
Sat May 01 00:00:00 EDT 1982
· Inorg. Chem.; (United States)
·
OSTI ID:5261128
Anion radical oxidation of nickel(II) macrocyclic complexes. Pulse radiolysis of (2,12-dimethyl-3,7,11,17-tetraazabicyclo(11. 3. 1)heptadeca-1(17),13,15-triene)nickel(II) in sodium bromide solution
Journal Article
·
Fri May 01 00:00:00 EDT 1981
· Inorg. Chem.; (United States)
·
OSTI ID:6399438
Redox reactivity of bis(1,4,7-triazacyclononane)iron(II/III) complexes in alkaline solution and characterization of a deprotonated species: Amidoiron(III) vs aminyliron(II) ground-state formulation. EPR, kinetic, pulse radiolysis, and laser photolysis study. [Electrons]
Journal Article
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Tue Feb 09 23:00:00 EST 1988
· Inorganic Chemistry; (USA)
·
OSTI ID:5612633
Related Subjects
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400201 -- Chemical & Physicochemical Properties
400301 -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
400600* -- Radiation Chemistry
ANTITHYROID DRUGS
AQUEOUS SOLUTIONS
BROMIDES
BROMINE COMPOUNDS
CARBONIC ACID DERIVATIVES
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHEMISTRY
COMPLEXES
DATA
DECOMPOSITION
DISPERSIONS
DRUGS
EXPERIMENTAL DATA
HALIDES
HALOGEN COMPOUNDS
HETEROCYCLIC COMPOUNDS
HORMONE ANTAGONISTS
HYDROGEN COMPOUNDS
HYDROXYL RADICALS
INFORMATION
KINETICS
LIGANDS
MIXTURES
NICKEL COMPLEXES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXIDATION
OXYGEN COMPOUNDS
PH VALUE
RADIATION CHEMISTRY
RADIATION EFFECTS
RADICALS
RADIOLYSIS
REACTION INTERMEDIATES
REACTION KINETICS
SOLUTIONS
THIOCYANATES
TRANSITION ELEMENT COMPLEXES
WATER
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400201 -- Chemical & Physicochemical Properties
400301 -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
400600* -- Radiation Chemistry
ANTITHYROID DRUGS
AQUEOUS SOLUTIONS
BROMIDES
BROMINE COMPOUNDS
CARBONIC ACID DERIVATIVES
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHEMISTRY
COMPLEXES
DATA
DECOMPOSITION
DISPERSIONS
DRUGS
EXPERIMENTAL DATA
HALIDES
HALOGEN COMPOUNDS
HETEROCYCLIC COMPOUNDS
HORMONE ANTAGONISTS
HYDROGEN COMPOUNDS
HYDROXYL RADICALS
INFORMATION
KINETICS
LIGANDS
MIXTURES
NICKEL COMPLEXES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXIDATION
OXYGEN COMPOUNDS
PH VALUE
RADIATION CHEMISTRY
RADIATION EFFECTS
RADICALS
RADIOLYSIS
REACTION INTERMEDIATES
REACTION KINETICS
SOLUTIONS
THIOCYANATES
TRANSITION ELEMENT COMPLEXES
WATER