We report the synthesis, electronic properties, and second-order nonlinear optical (NLO) response of asymmetric heteronuclear push-pull bimetallic complexes with pyrazine (pyz) and trans-1,2-bis(4-pyridyl)ethylene (BPE) as polarizable linkers, connecting the "W(CO)5" fragment (acting as donor group) and "cis-Rh(CO)2Cl", "cis-Re(CO)4Cl", and BF3 fragments (acting as acceptor groups). The second-order NLO response was assessed by the EFISH technique (βvec), working with a nonresonant incident wavelength of 1.907 μm and by solvatochromic studies (βCT). These results are compared with the behavior of mononuclear [W(CO)5L] complexes (L = pyridine or torss-stilbazole para substituted with acceptor groups) and of classical structurally related organic push-pull aromatic chromophores. The second-order NLO response of asymmetric chromophores with BPE as linker is comparable, with the exception of the sign, to classical push-pull stilbenic compounds. However when pyrazine is the linker, the response can be higher (BF3 as acceptor group) or higher but with opposite sign ("cis-Rh(CO)2Cl" as acceptor group) than the related push-pull benzenic chromophores. Only with a pyrazine linker and "cis-Re(CO)4Cl" as acceptor does the second-order NLO response becomes irrelevant. The above results are interpreted assuming that the MLCT (W → π*L) transition, originating from the "W(CO)5" moiety, dominates the second-order response of these push-pull heteronuclear dimeric chromophores.

Organometallic Counterparts of Push−Pull Aromatic Chromophores for Nonlinear Optics:  Push−Pull Heteronuclear Bimetallic Complexes with Pyrazine andtrans-1,2-Bis(4-pyridyl)ethylene as Linkers / M. Pizzotti, R. Ugo, D. Roberto, S. Bruni, P. Fantucci, C. Rovizzi. - In: ORGANOMETALLICS. - ISSN 0276-7333. - 21:26(2002), pp. 5830-5840.

Organometallic Counterparts of Push−Pull Aromatic Chromophores for Nonlinear Optics:  Push−Pull Heteronuclear Bimetallic Complexes with Pyrazine andtrans-1,2-Bis(4-pyridyl)ethylene as Linkers

M. Pizzotti
Primo
;
R. Ugo
Secondo
;
D. Roberto;S. Bruni;
2002

Abstract

We report the synthesis, electronic properties, and second-order nonlinear optical (NLO) response of asymmetric heteronuclear push-pull bimetallic complexes with pyrazine (pyz) and trans-1,2-bis(4-pyridyl)ethylene (BPE) as polarizable linkers, connecting the "W(CO)5" fragment (acting as donor group) and "cis-Rh(CO)2Cl", "cis-Re(CO)4Cl", and BF3 fragments (acting as acceptor groups). The second-order NLO response was assessed by the EFISH technique (βvec), working with a nonresonant incident wavelength of 1.907 μm and by solvatochromic studies (βCT). These results are compared with the behavior of mononuclear [W(CO)5L] complexes (L = pyridine or torss-stilbazole para substituted with acceptor groups) and of classical structurally related organic push-pull aromatic chromophores. The second-order NLO response of asymmetric chromophores with BPE as linker is comparable, with the exception of the sign, to classical push-pull stilbenic compounds. However when pyrazine is the linker, the response can be higher (BF3 as acceptor group) or higher but with opposite sign ("cis-Rh(CO)2Cl" as acceptor group) than the related push-pull benzenic chromophores. Only with a pyrazine linker and "cis-Re(CO)4Cl" as acceptor does the second-order NLO response becomes irrelevant. The above results are interpreted assuming that the MLCT (W → π*L) transition, originating from the "W(CO)5" moiety, dominates the second-order response of these push-pull heteronuclear dimeric chromophores.
Settore CHIM/03 - Chimica Generale e Inorganica
Article (author)
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS 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: http://hdl.handle.net/2434/182012
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 46
  • ???jsp.display-item.citation.isi??? 41
social impact