Pulse and continuous radiolysis of cyano-bridged polynuclear ruthenium complexes in aqueous solution

Journal Article · Thu Jan 26 04:00:00 EST 1989 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100339a046· OSTI ID:5446966

Mulazzani, Q G; Venturi, M; D'Angelantonio, M; Bignozzi, C A; Scandola, F ^[1]

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1. Istituto di Fotochimiica e Radiazioni d'Alta Energia del C.N.R., Bologna (Italy)

The reactions of e{sub aq}{sup {minus}} and CO{sub 2}{sup {sm bullet}{minus}} radicals with ((NH{sub 3}){sub 5}RuNCRu(bpy){sub 2}CNRu(NH{sub 3}){sub 5}){sup 6+} (3,2,3), (py(NH{sub 3}){sub 4}RuNCRu-(bpy){sub 2}CNRu(NH{sub 3}){sub 5}){sup 6+} (3',2,3), and (py(NH{sub 3}){sub 4}RuNCRu(bpy){sub 2}CNRu(NH{sub 3}){sub 4}py){sup 6+} (3',2,3') in aqueous solution result in the formation of the reduced forms (2,2,3), (2',2,3), and (2',2,3'), respectively; exhaustive irradiation results in the formation of the (2,2,2), (2',2,2), and (2',2,2') species, respectively. The rate constants for the reduction of the three Ru(III)Ru(II)Ru(III) complexes by e{sub aq}{sup {minus}} and by CO{sub 2}{sup {sm bullet}{minus}} radicals are {approximately} 3 {times} 10{sup 10} and (1.4 {plus minus} 0.2) {times} 10{sup 10} M{sup {minus}1} s{sup {minus}1}, respectively, independent of the nature of the complex. In acidic solution and in the presence of tert-butyl alcohol, the reaction between H{sup {sm bullet}} radicals and (3,2,3), for which k = (4.0 {plus minus} 0.5) {times} 10{sup 9} M{sup {minus}1} s{sup {minus}1}, also results in the formation of (2,2,3); under these conditions, the formation of (2,2,2) was not observed. The intramolecular electron-transfer reaction (3',2,2) {yields} (2',2,3), which is believed to follow the formation of (3',2,2), obtained in parallel with (2',2,3) from the reduction of (3',2,3), was not directly observed, indicating that the associated rate constant has a value of k {>=} 5 {times} 10{sup 7} s{sup {minus}1}.

• OSTI ID: 5446966
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 93:2; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400600* -- Radiation Chemistry
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHEMISTRY
COMPLEXES
DATA
DECOMPOSITION
ELECTRON TRANSFER
ELECTRONS
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
FERMIONS
HYDROGEN COMPOUNDS
INFORMATION
INORGANIC ACIDS
IRRADIATION
KINETICS
LEPTONS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PH VALUE
PULSED IRRADIATION
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIOLYSIS
REACTION KINETICS
RUTHENIUM COMPLEXES
SOLVATED ELECTRONS
TRANSITION ELEMENT COMPLEXES