Electronic Delocalization in Coordination Polymers Based on Bimetallic Carboxylates

Computational methods (DFT at the B3LYP, PBE0 and m06 levels, MO fragments decomposition, and the broken symmetry approach) have been used to evaluate the influence of the bridging ligand (BL) on the extent of electron delocalization in coordination polymers based on diruthenium tetracarboxylates. T...

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Detalhes bibliográficos
Autores: Castro, Maria Ana, Roitberg, Esteban Gabriel, Cukiernik, Fabio Daniel
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2013
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositório:CONICET Digital (CONICET)
Idioma:inglês
OAI Identifier:oai:ri.conicet.gov.ar:11336/7802
Acesso em linha:http://hdl.handle.net/11336/7802
Access Level:Acceso aberto
Palavra-chave:Coordination Polymers
Electronic Delocalization
Diruthenium Carboxylates
Tetrazine
Broken Symmetry
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descrição
Resumo:Computational methods (DFT at the B3LYP, PBE0 and m06 levels, MO fragments decomposition, and the broken symmetry approach) have been used to evaluate the influence of the bridging ligand (BL) on the extent of electron delocalization in coordination polymers based on diruthenium tetracarboxylates. The efficiency of three different nitrogenated axial ligands, namely pyrazine (pz), phenazine (phz), and tetrazine (tz), to mediate electron coupling between Ru2(II,II) or Ru2(II,III) centers has been estimated through four different parameters: calculated Ru-N distances, HOMO-LUMO gaps, HOMO and LUMO compositions, and magnetic coupling constants J. All these parameters pointed toward a coordination polymer based on Ru2(II,II) centers axially linked by tetrazine being the best candidate for exhibiting electron delocalization through the Ru2−BL framework. Such a compound has been synthesized and characterized; its vis-NIR spectrum exhibited the predicted features, mainly an intense low-energy MLCT band, assigned to the expected Ru2(II,II) - tz process associated with electron delocalization.