File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Density functional theory studies of [Fe(O)2L]2+: What is the role of the spectator ligand L with different coordination numbers?

TitleDensity functional theory studies of [Fe(O)2L]2+: What is the role of the spectator ligand L with different coordination numbers?
Authors
KeywordsAmines
Density functional calculations
High-valency
Iron
Oxido ligands
Issue Date2010
PublisherWiley - V C H Verlag GmbH & Co KGaA. The Journal's web site is located at http://www.eurjic.org
Citation
European Journal Of Inorganic Chemistry, 2010 n. 32, p. 5113-5123 How to Cite?
AbstractDensity functional theory (DFT) studies were carried out on [Fe(O) 2(L)]n+ [L = qpy (1), simple amines (2), and tpy (3); qpy = 2,2′:6′,2″:6″,2‴′:6‴′, 2‴′-quinquepyridine and tpy = terpyridine; n = 1 or 2] to study how the coordination number of the spectator ligand L affects the geometries and electronic structures of the complexes. It was found that qpy can act as both a tridentate and pentadentate ligand resulting in [Fe(O)2(qpy)] 2+ (12+) having a trigonal bipyramidal (TBP) geometry in the former case, and a pentagonal bipyramidal (PBP) geometry in the latter case. The difference in coordination geometries has a significant impact on the electronic structures of 12+. With a TBP geometry, 12+ adopts a [FeV(O)2(qpy)+•]2+ formalism where a d3 quartet FeV ion ferromagnetically and antiferromagnetically couples to the qpy cation radical to give close-lying triplet and quintet states (within ca. 0.2 eV). With a PBP geometry, the Fe V ion in 12+ also formally has three unpaired electrons (a d3 quartet) with the fourth unpaired electron localized on a single oxido ligand to give a quintet state. The unoccupied orbital of 12+ in PBP geometry is lower lying in energy and has higher oxido character than when the complex has TBP geometry. Thus, based on the MO energies and oxido character of the unoccupied orbital, 12+ with PBP geometry is proposed to be a more reactive oxidant than 12+ with TBP geometry. On the other hand, 12+ with TBP geometry has a similar electronic structure to heme Cpd I, and it is possible that these two compounds have similar oxygen atom transfer reaction mechanisms. By varying the ligand coordination number using different spectator ligands L, the dioxido-iron complex [Fe(O)2(L)]2+ can change from a high-spin triplet when L = tpy, to a low-spin singlet when L = simple amines, to a quasi-degenerate triplet and quintet state when L = qpy. The electronic structures of [Fe(O)2L]2+ complexes, where L has different coordination numbers, have been studied with DFT. Ligand qpy can act as both a penta- and tridentate ligand. The LUMO of the former has higher oxido character and a lower orbital energy than the latter. The latter coordination geometry also has a similar electronic structure to heme Cpd I, suggesting possibly similar oxygen atom transfer reaction mechanisms for these complexes. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Persistent Identifierhttp://hdl.handle.net/10722/134385
ISSN
2015 Impact Factor: 2.686
2015 SCImago Journal Rankings: 1.018
ISI Accession Number ID
Funding AgencyGrant Number
University Grants CouncilHKU 700906
University Grants Committee of Hong Kong, SAR of ChinaAoE/P1-0/01
University of Hong Kong
Funding Information:

This work was supported by the University Grants Council (HKU 700906) and the University Grants Committee of Hong Kong, SAR of China (Area of Excellence Scheme AoE/P1-0/01) C -M C would like to thank the University Development Fund of the University of Hong Kong for financial support The authors also thank the Computer Center at the University of Hong Kong for providing supercomputer time

References

 

DC FieldValueLanguage
dc.contributor.authorTong, GSMen_HK
dc.contributor.authorChe, CMen_HK
dc.date.accessioned2011-06-17T09:18:51Z-
dc.date.available2011-06-17T09:18:51Z-
dc.date.issued2010en_HK
dc.identifier.citationEuropean Journal Of Inorganic Chemistry, 2010 n. 32, p. 5113-5123en_HK
dc.identifier.issn1434-1948en_HK
dc.identifier.urihttp://hdl.handle.net/10722/134385-
dc.description.abstractDensity functional theory (DFT) studies were carried out on [Fe(O) 2(L)]n+ [L = qpy (1), simple amines (2), and tpy (3); qpy = 2,2′:6′,2″:6″,2‴′:6‴′, 2‴′-quinquepyridine and tpy = terpyridine; n = 1 or 2] to study how the coordination number of the spectator ligand L affects the geometries and electronic structures of the complexes. It was found that qpy can act as both a tridentate and pentadentate ligand resulting in [Fe(O)2(qpy)] 2+ (12+) having a trigonal bipyramidal (TBP) geometry in the former case, and a pentagonal bipyramidal (PBP) geometry in the latter case. The difference in coordination geometries has a significant impact on the electronic structures of 12+. With a TBP geometry, 12+ adopts a [FeV(O)2(qpy)+•]2+ formalism where a d3 quartet FeV ion ferromagnetically and antiferromagnetically couples to the qpy cation radical to give close-lying triplet and quintet states (within ca. 0.2 eV). With a PBP geometry, the Fe V ion in 12+ also formally has three unpaired electrons (a d3 quartet) with the fourth unpaired electron localized on a single oxido ligand to give a quintet state. The unoccupied orbital of 12+ in PBP geometry is lower lying in energy and has higher oxido character than when the complex has TBP geometry. Thus, based on the MO energies and oxido character of the unoccupied orbital, 12+ with PBP geometry is proposed to be a more reactive oxidant than 12+ with TBP geometry. On the other hand, 12+ with TBP geometry has a similar electronic structure to heme Cpd I, and it is possible that these two compounds have similar oxygen atom transfer reaction mechanisms. By varying the ligand coordination number using different spectator ligands L, the dioxido-iron complex [Fe(O)2(L)]2+ can change from a high-spin triplet when L = tpy, to a low-spin singlet when L = simple amines, to a quasi-degenerate triplet and quintet state when L = qpy. The electronic structures of [Fe(O)2L]2+ complexes, where L has different coordination numbers, have been studied with DFT. Ligand qpy can act as both a penta- and tridentate ligand. The LUMO of the former has higher oxido character and a lower orbital energy than the latter. The latter coordination geometry also has a similar electronic structure to heme Cpd I, suggesting possibly similar oxygen atom transfer reaction mechanisms for these complexes. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.en_HK
dc.languageengen_US
dc.publisherWiley - V C H Verlag GmbH & Co KGaA. The Journal's web site is located at http://www.eurjic.orgen_HK
dc.relation.ispartofEuropean Journal of Inorganic Chemistryen_HK
dc.subjectAminesen_HK
dc.subjectDensity functional calculationsen_HK
dc.subjectHigh-valencyen_HK
dc.subjectIronen_HK
dc.subjectOxido ligandsen_HK
dc.titleDensity functional theory studies of [Fe(O)2L]2+: What is the role of the spectator ligand L with different coordination numbers?en_HK
dc.typeArticleen_HK
dc.identifier.openurlhttp://library.hku.hk:4550/resserv?sid=HKU:IR&issn=1434-1948&volume=2010&issue=32&spage=5113&epage=5123&date=2010&atitle=Density+functional+theory+studies+of+[Fe(O)2L]2+:+What+is+the+role+of+the+spectator+ligand+L+with+different+coordination+numbers?-
dc.identifier.emailTong, GSM:tongsm@hkucc.hku.hken_HK
dc.identifier.emailChe, CM:cmche@hku.hken_HK
dc.identifier.authorityTong, GSM=rp00790en_HK
dc.identifier.authorityChe, CM=rp00670en_HK
dc.description.naturelink_to_subscribed_fulltext-
dc.identifier.doi10.1002/ejic.201000656en_HK
dc.identifier.scopuseid_2-s2.0-78249279958en_HK
dc.identifier.hkuros185842en_US
dc.relation.referenceshttp://www.scopus.com/mlt/select.url?eid=2-s2.0-78249279958&selection=ref&src=s&origin=recordpageen_HK
dc.identifier.volume2010en_US
dc.identifier.issue32en_HK
dc.identifier.spage5113en_HK
dc.identifier.epage5123en_HK
dc.identifier.isiWOS:000285041600009-
dc.publisher.placeGermanyen_HK
dc.identifier.scopusauthoridTong, GSM=7102328656en_HK
dc.identifier.scopusauthoridChe, CM=7102442791en_HK

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats