Weak forces at work in dye-loaded zeolite materials: spectroscopic investigation on cation-sulfur interactions
Giorgio Macchi1, Chiara Botta, Gion Calzaferri
1Università degli Studi di Milano Bicocca and INFM, Dipartimento di Scienza dei Materiali, via R.Cozzi 53, I-20125 Milano, Italy. giorgio.macchi@mater.unimib.it
Abstract:
The interaction between sulfur-containing chromophores and cationic species (K(+)) has been investigated in dye-loaded zeolite materials by means of photoluminescence spectroscopy. A red-shift in the emission spectra of the host-guest compounds (HGCs) has been detected and unambiguously connected to the close proximity between a conjugated moiety and nearby free charges, suggesting a specific role played by sulfur lone pair electrons. Quantum-chemical calculations on model compounds have been performed to support this hypothesis.
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