Acknowledgements
-
PV < Si MCM 41 (high loaded)
-
-
-
< Si MCM 41 (low loaded)
-
Funding of this work by the Deutsche Forschungsgemeinschaft
(WO 237/16-3) is gratefully acknowledged.
(4.2)
-
< HY < DAY
Due to the weak interactions and the absence of acidic sites
in poly(vinyl acetate) (PV) the dye can readily undergo all
rotational movements, which are necessary for the attainment
of the thermodynamic equilibrium, i.e. the relaxation to the
closed SP form (Fig. 3). For the molecular sieves the acidity of
the host materials and the local polarities around the dye
molecules in the cages and channels are decisive parameters to
explain the order given above. The average local polarity of the
environment for a dye-molecule in a high-loaded molecular
sieve (HY) is lower compared to a low-loaded composite
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½
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t ) is largest in the small faujasite supercages compared to the
½
wide channel-structured Si-MCM-41 or to SiO2 matrices
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½
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2020
J. Mater. Chem., 2001, 11, 2014–2021