DC Field | Value | Language |
---|---|---|
dc.contributor.author | Yang, X | ko |
dc.contributor.author | Baik, Mu-Hyun | ko |
dc.date.accessioned | 2016-04-12T07:44:49Z | - |
dc.date.available | 2016-04-12T07:44:49Z | - |
dc.date.created | 2015-09-11 | - |
dc.date.created | 2015-09-11 | - |
dc.date.issued | 2006-06 | - |
dc.identifier.citation | JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, v.128, no.23, pp.7476 - 7485 | - |
dc.identifier.issn | 0002-7863 | - |
dc.identifier.uri | http://hdl.handle.net/10203/203345 | - |
dc.description.abstract | The mechanism of the catalytic oxidation of water by cis, cis-[(bpy)(2)Ru(OH2)](2)O4+ to give molecular dioxygen was investigated using Density Functional Theory ( DFT). A series of four oxidation and four deprotonation events generate the catalytically competent species cis, cis-[(bpy)(2)(RuO)-O-V](2)O4+, which breaks the H-OH bond homolytically at the rate determining transition state to give a hydroperoxo intermediate. Our calculations predict a rate determining activation barrier of 25.9 kcal/mol in solution phase, which is in reasonable agreement with the previously reported experimental estimate of 18.7-23.3 kcal/mol. A number of plausible coupling schemes of the two metal sites including strong coupling, weak ferromagnetic and weak antiferromagnetic coupling have been considered. In addition, both high-spin and low-spin states at each of the Ru(V)-d(3) centers were explored and we found that the high-spin states play an important mechanistic role. Our calculations suggest that cis, cis-[(bpy)(2)(RuO)-O-V](2)O4+ performs formally an intramolecular ligand-to-metal charge transfer when reacting with water to formally give a cis, cis-[(bpy)(2)(RuO)-O-IV center dot](2)O4+ complex. We propose that the key characteristic of the diruthenium catalyst that allows it to accomplish the most difficult first two oxidations of the overall four-electron redox reaction is directly associated with this in situ generation of two radicaloid oxo moieties that promote the water splitting reaction. A proton coupled metal-to-metal charge transfer follows to yield a Ru(V)/Ru(III) peroxo/aqua mixed valence complex, which performs the third redox reaction to give the superoxo/aqua complex. Finally, intersystem crossing to a ferromagnetically coupled Ru(IV)/Ru(III) superoxo/aqua species is predicted, which will then promote the last redox event to release triplet dioxygen as the final product. A number of key features of the computed mechanism are explored in detail to derive a conceptual understanding of the catalytic mechanism. | - |
dc.language | English | - |
dc.publisher | AMER CHEMICAL SOC | - |
dc.subject | POISSON-BOLTZMANN EQUATION | - |
dc.subject | EFFECTIVE CORE POTENTIALS | - |
dc.subject | NONHEME DIIRON ENZYMES | - |
dc.subject | MU-OXO DIMER | - |
dc.subject | MOLECULAR CALCULATIONS | - |
dc.subject | METHANE MONOOXYGENASE | - |
dc.subject | PHOTOSYSTEM-II | - |
dc.subject | INTERMEDIATE-Q | - |
dc.subject | ION | - |
dc.subject | DIOXYGEN | - |
dc.title | cis,cis-[(bpy)(2)(RuO)-O-V](2)O4+ catalyzes water oxidation formally via in situ generation of radicaloid Ru-IV-O center dot | - |
dc.type | Article | - |
dc.identifier.wosid | 000238099500034 | - |
dc.identifier.scopusid | 2-s2.0-33745036344 | - |
dc.type.rims | ART | - |
dc.citation.volume | 128 | - |
dc.citation.issue | 23 | - |
dc.citation.beginningpage | 7476 | - |
dc.citation.endingpage | 7485 | - |
dc.citation.publicationname | JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | - |
dc.identifier.doi | 10.1021/ja053710j | - |
dc.contributor.localauthor | Baik, Mu-Hyun | - |
dc.contributor.nonIdAuthor | Yang, X | - |
dc.type.journalArticle | Article | - |
dc.subject.keywordPlus | POISSON-BOLTZMANN EQUATION | - |
dc.subject.keywordPlus | EFFECTIVE CORE POTENTIALS | - |
dc.subject.keywordPlus | NONHEME DIIRON ENZYMES | - |
dc.subject.keywordPlus | MU-OXO DIMER | - |
dc.subject.keywordPlus | MOLECULAR CALCULATIONS | - |
dc.subject.keywordPlus | METHANE MONOOXYGENASE | - |
dc.subject.keywordPlus | PHOTOSYSTEM-II | - |
dc.subject.keywordPlus | INTERMEDIATE-Q | - |
dc.subject.keywordPlus | ION | - |
dc.subject.keywordPlus | DIOXYGEN | - |
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