Tripods of general formula R'-O-CH(2)C(CH(2)OH)(3) are excellent site-specific ligands for the preparation of functionalized Fe(4) single-molecule magnets. Herein, we describe the synthesis and characterization of two novel complexes designed to bind graphene surfaces, in which the R group consists of an alkyl spacer -(CH(2))(n)- (n = 6 and 10) and a terminal pyrenyl moiety. The site-specific ligand substitution on [Fe(4)(O-Me)(6)(dpm)(6)] (Hdpm = dipivaloylmethane) with the new tripods has been studied with (2)H NMR on isotopically-enriched samples, revealing that, once formed, these clusters are stable in solution over long timescales. It was not possible to isolate the new compounds as crystalline solids, nevertheless they were chemically characterized by elemental analysis and (1)H NMR. The presence of the pyrenyl ending groups prompted us to investigate the effect of metal complexation on fluorescence, and a full pyrene-to-iron cluster excitation energy transfer was observed. The analysis of the magnetic behaviour revealed an S = 5 ground spin state with a negative zero-field splitting parameter D = -0.42 cm(-1).

A novel class of tetrairon(III) single-molecule magnets with graphene-binding groups / C.Danieli;A.Cornia;C.Cecchelli;R.Sessoli;AL.Barra;G.Ponterini;B.Zanfrognini. - In: POLYHEDRON. - ISSN 0277-5387. - STAMPA. - 28:(2009), pp. 2029-2035. [10.1016/j.poly.2008.12.024]

A novel class of tetrairon(III) single-molecule magnets with graphene-binding groups

SESSOLI, ROBERTA;
2009

Abstract

Tripods of general formula R'-O-CH(2)C(CH(2)OH)(3) are excellent site-specific ligands for the preparation of functionalized Fe(4) single-molecule magnets. Herein, we describe the synthesis and characterization of two novel complexes designed to bind graphene surfaces, in which the R group consists of an alkyl spacer -(CH(2))(n)- (n = 6 and 10) and a terminal pyrenyl moiety. The site-specific ligand substitution on [Fe(4)(O-Me)(6)(dpm)(6)] (Hdpm = dipivaloylmethane) with the new tripods has been studied with (2)H NMR on isotopically-enriched samples, revealing that, once formed, these clusters are stable in solution over long timescales. It was not possible to isolate the new compounds as crystalline solids, nevertheless they were chemically characterized by elemental analysis and (1)H NMR. The presence of the pyrenyl ending groups prompted us to investigate the effect of metal complexation on fluorescence, and a full pyrene-to-iron cluster excitation energy transfer was observed. The analysis of the magnetic behaviour revealed an S = 5 ground spin state with a negative zero-field splitting parameter D = -0.42 cm(-1).
28
2029
2035
C.Danieli;A.Cornia;C.Cecchelli;R.Sessoli;AL.Barra;G.Ponterini;B.Zanfrognini
File in questo prodotto:
File Dimensione Formato  
Polyhedron_2009.pdf

Accesso chiuso

Descrizione: Polyhedron_2009
Tipologia: Pdf editoriale (Version of record)
Licenza: DRM non definito
Dimensione 391.65 kB
Formato Adobe PDF
391.65 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2158/370335
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 9
  • ???jsp.display-item.citation.isi??? 7
social impact