DC Field | Value | Language |
---|---|---|
dc.contributor.author | Belanzoni, P | - |
dc.contributor.author | Bernasconi, L | - |
dc.contributor.author | Baerends, EJ | - |
dc.contributor.author | null | - |
dc.date.accessioned | 2016-04-01T08:23:45Z | - |
dc.date.available | 2016-04-01T08:23:45Z | - |
dc.date.issued | 2009-10 | - |
dc.identifier.citation | JOURNAL OF PHYSICAL CHEMISTRY A | - |
dc.identifier.citation | v.113 | - |
dc.identifier.citation | no.43 | - |
dc.identifier.citation | pp.11926-11937 | - |
dc.identifier.issn | 1089-5639 | - |
dc.identifier.other | 2009-OAK-0000019208 | - |
dc.identifier.uri | https://oasis.postech.ac.kr/handle/2014.oak/27874 | - |
dc.description.abstract | We study the cleavage Of O-2 in gas phase [(EDTAH)Fe(O-2)Fe(EDTAH)](2-) a proposed intermediate in the aqueous Fe(II)-to-Fe(III) autoxidation reaction in the presence of atmospheric dioxygen and EDTA ligand. The role of the exchange coupling between the locally high-spin Fe centers in the O-O dissociation is investigated. Using results from broken symmetry (BS) density functional theory (DFT) calculations, we show that the system can be modeled as two high-spin (HS) S = 5/2 Fe(III) d(5) centers coupled through a bridging peroxo O-2(2-) ligand, consistent with hypotheses advanced in the literature. We show that in this electronic configuration the O-O cleavage reaction is forbidden by (spin) symmetry. Dissociation of the O-2(2-) group to the product ground state may only take place if the system is allowed to undergo a transition to a state of lower spin multiplicity (S = 4) as the O-O bond is stretched. We show that the exchange coupling between the two Fe ions in [(EDTAH)Fe(O-2)Fe(EDTAH)](2-) plays only a minor role in defining the chemistry Of O-2 activation in this system. The peroxo/oxo interconversion involves a state outside the Heisenberg spin ladder of the initial S = .5 state. In this S = 4 state, the dinuclear complex evolves to two oxo complexes, [EDTAH center dot Fe(IV)O](-), with an overall energy barrier of only similar to 86 kJ mol(-1). According to recent theoretical work, the latter species are exceptionally strong oxidants, making them ideal candidate catalysts for organic oxidations (including C-H bond hydroxylation). We highlight the (spin) symmetry forbidden nature of the reaction on the S = 5 surface and its symmetry allowed character in the electronic configuration with S = 4. | - |
dc.description.statementofresponsibility | X | - |
dc.publisher | AMER CHEMICAL SOC | - |
dc.subject | DENSITY-FUNCTIONAL THEORY | - |
dc.subject | VALENCE BOND THEORY | - |
dc.subject | TAURINE/ALPHA-KETOGLUTARATE DIOXYGENASE | - |
dc.subject | ELECTRON-PARAMAGNETIC-RESONANCE | - |
dc.subject | HORSERADISH-PEROXIDASE COMPOUND | - |
dc.subject | REDUCTASE-INTERMEDIATE-X | - |
dc.subject | TRANSITION-METAL DIMERS | - |
dc.subject | 2-FE FERREDOXIN MODELS | - |
dc.subject | NONHEME IRON ENZYMES | - |
dc.subject | ACTIVE-SITE MODELS | - |
dc.title | O-2 Activation in a Dinuclear Fe(II)/EDTA Complex: Spin Surface Crossing As a Route to Highly Reactive Fe(IV)oxo Species | - |
dc.type | Article | - |
dc.identifier.doi | 10.1021/JP9033672 | - |
dc.author.google | Belanzoni, P | - |
dc.author.google | Bernasconi, L | - |
dc.author.google | Baerends, EJ | - |
dc.relation.volume | 113 | - |
dc.relation.issue | 43 | - |
dc.relation.startpage | 11926 | - |
dc.relation.lastpage | 11937 | - |
dc.publisher.location | US | - |
dc.relation.journal | JOURNAL OF PHYSICAL CHEMISTRY A | - |
dc.relation.index | SCI급, SCOPUS 등재논문 | - |
dc.collections.name | Journal Papers | - |
dc.type.docType | Article | - |
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