http://www.cnr.it/ontology/cnr/individuo/prodotto/ID198065

Spirobifluorene Bridged Ir(III) and Os(II) Polypyridyl Arrays: Synthesis, Photophysical Characterization, and Energy Transfer Dynamics (Articolo in rivista)

Type

Articolo in rivista (Classe)
Prodotto della ricerca (Classe)

Label

Spirobifluorene Bridged Ir(III) and Os(II) Polypyridyl Arrays: Synthesis, Photophysical Characterization, and Energy Transfer Dynamics (Articolo in rivista) (literal)

Anno

2012-01-01T00:00:00+01:00 (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#doi

10.1021/ic201903g (literal)

Alternative label

Barbara Ventura, Andrea Barbieri, Alessandra Degli Esposti, Julie Batcha Seneclauze, and Raymond Ziessel (2012)
Spirobifluorene Bridged Ir(III) and Os(II) Polypyridyl Arrays: Synthesis, Photophysical Characterization, and Energy Transfer Dynamics
in Inorganic chemistry; ACS, American chemical society, Washington, DC (Stati Uniti d'America)
(literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori

Barbara Ventura, Andrea Barbieri, Alessandra Degli Esposti, Julie Batcha Seneclauze, and Raymond Ziessel (literal)

Pagina inizio

2832 (literal)

Pagina fine

2840 (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#url

http://dx.doi.org/10.1021/ic201903g (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume

51 (literal)

Rivista

Inorganic chemistry (Rivista)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#pagineTotali

9 (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroFascicolo

5 (literal)

Note

ISI Web of Science (WOS) (literal)
Scopu (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni

Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche (ISOF-CNR), Via P. Gobetti 101, 40129 Bologna, Italy Laboratoire de Chimie Organique et Spectroscopies Avancées (LCOSA) associé au CNRS (UMR 7515) École, de Chimie, Polymères, Matériaux (ECPM), Université de Strasbourg (UdS), 25 rue Becquerel, 67087 Strasbourg Cedex 02, France (literal)

Titolo

Spirobifluorene Bridged Ir(III) and Os(II) Polypyridyl Arrays: Synthesis, Photophysical Characterization, and Energy Transfer Dynamics (literal)

Abstract

The synthesis, characterization, photophysics, and time-dependent density functional theory (TD-DFT) calculations of spirobifluorene-bipyridine based iridium(III), osmium(II), and mixed Ir/Os complexes are presented. The preparation of the reference and mixed complexes proceeded step-by-step and microwave irradiation facilitated the complexation of osmium. The absorption of the target heterobimetallic derivative, Ir-L-Os, is described by linear combination of half of the absorption spectra of the homobimetallic analogues, Ir-L-Ir and Os-L-Os, due to the occurrence of mixed ligand and metal based transitions when the spirobifluorene-(bpy)2 bridging ligand L is linked to the metal, confirming a negligible interaction between the substituted metallic chromophores. TD-DFT calculations on monometallic, homo- and hetero-bimetallic complexes fully disentangled the origin of the absorption features. Noticeably, in the mixed Ir-L-Os complex an almost quantitative energy transfer from the 3Ir to the 3Os MLCT state is occurring, with a rate constant of 4.1 × 108 s-1 and nearly exclusively via a Dexter-type mechanism mediated by the orbitals of the spiroconjugated ligand. This result, together with the outcomes of the TD-DFT calculations, supports the existence of spiroconjugation and evidences the interesting role of this kind of bridge in the energy transfer dynamics of the arrays. In all the complexes, moreover, the ligand fluorescence is heavily quenched by energy transfer processes toward the metallic appended units; the rate constant is estimated in the order of 1010 s-1 for Ir-L-Os and higher than 1012 s-1 for the other complexes. In the heterometallic array, both at room temperature and at 77 K, all photons are thus funneled to the emissive Os 3MLCT state, which acts as energy trap for the antenna cascade. (literal)

Editore