The complex 2,(3)-tetrabromo-3,(2) -tetra[(3,5-di-tert-butyl)phenyloxy]-naphthalocvaninato lead [Br(4)(tBu(2)C(6)H(3)O)(4)NcPb, 1] has been prepared and its optical limiting properties for ns light pulses have been measured. Complex 1 behaves as a reverse saturable absorber within the spectral range 440-720 nm with a limiting threshold of 0.1 J cm(-2) at 532 nm. The lifetime of the absorbing triplet excited state has been evaluated as 3.8x10(-7) s and the quantum yield of triplet formation has been measured as 0.07 in toluene. The nonlinear optical transmission properties of complex 1 have also been determined in Plexiglas [naphthalocyanine content: 5.0x10(-4) M (0.1% by weight)]. A reversible nonlinear absorption was again observed for a fluence above 0.4 Jcm(-2), but through different excited-state dynamics. This may be rationalized in terms of aggregation of the molecule in the polymer matrix.
Tetrabrominated Lead Naphthalocyanine for Optical Power Limiting / Dini, Danilo; Moreno, Meneghetti; M. J. F., Calvete; Thomas, Arndt; Colin, Liddiard; Michael, Hanack. - In: CHEMISTRY-A EUROPEAN JOURNAL. - ISSN 0947-6539. - 16:4(2010), pp. 1212-1220. [10.1002/chem.200901499]
Tetrabrominated Lead Naphthalocyanine for Optical Power Limiting
DINI, DANILO;
2010
Abstract
The complex 2,(3)-tetrabromo-3,(2) -tetra[(3,5-di-tert-butyl)phenyloxy]-naphthalocvaninato lead [Br(4)(tBu(2)C(6)H(3)O)(4)NcPb, 1] has been prepared and its optical limiting properties for ns light pulses have been measured. Complex 1 behaves as a reverse saturable absorber within the spectral range 440-720 nm with a limiting threshold of 0.1 J cm(-2) at 532 nm. The lifetime of the absorbing triplet excited state has been evaluated as 3.8x10(-7) s and the quantum yield of triplet formation has been measured as 0.07 in toluene. The nonlinear optical transmission properties of complex 1 have also been determined in Plexiglas [naphthalocyanine content: 5.0x10(-4) M (0.1% by weight)]. A reversible nonlinear absorption was again observed for a fluence above 0.4 Jcm(-2), but through different excited-state dynamics. This may be rationalized in terms of aggregation of the molecule in the polymer matrix.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
