structural unit is a very useful building block to construct
highly efficient TPA materials with an excellent nonlinearity-
transparency trade-off.
This work was financially supported by Hong Kong
Research Grant Council, GRF, HKBU 202408.
Notes and references
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4 Normalized one- and two-photon excitation spectra of
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In summary, we have synthesized homologous series of
diphenylamino-endcapped oligofluorenes bearing different
substituents at the 9-position of fluorenyl rings, which exhibit
a high fluorescence quantum yield and a large two-photon
absorption cross section of up to 2559 GM at a 710 nm fs laser
pulse. Although the absorption and emission remain fairly
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ꢀc
This journal is The Royal Society of Chemistry 2009
Chem. Commun., 2009, 5421–5423 | 5423