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Several solvent-inventory experiments are conducted to explain the accumulated proton-donating ability of the different solvent molecules involved in proton transfer. The discussed deprotonation of the alcohol molecule is shown to be the main mechanism controlling the rate of the reaction.

The first example of a concentration-independent ultimate white-light-emitting molecule is presented based on excited-state intramolecular proton transfer materials. The molecule is composed of covalently linked blue- and orange-light-emitting moieties between which energy transfer is entirely frustrated, which has led to the formation of reproducible, stable white photo- and electroluminescence.

The preparation and evaluation of a novel calix[4]arene-based fluorescent chemosensor is described for detecting [Cd.sup.2+] and [Zn.sup.2+]. The changes observed for the fluorescent spectra upon addition of various metal ions show that chemosensor is highly selective for [Cd.sup.2+] and [Zn.sup.2+] over other metal ions.

Upon absorption of a photon, the 1-methyl-7-oxyquinolinium zwitterion in neutral water undergoes a proton-transfer cycle involving protonation at the lowest excited triplet state and redeprotonation at the ground state. On one hand, the proton transfer of a water molecule to the triplet-state zwitterion takes place on the time scale of 28 μs with an activation energy of 12.6 kJ mol−1. On the other hand, the ground-state redeprotonation occurs with a rate constant of (13 μs)−1, although its reverse reaction of protonation competes with a rate constant of (37 μs)−1. [ABSTRACT FROM AUTHOR]

The synthesis and evaluation of a novel calix[4]arene-based fluorescent chemosensor 8 for the detection of Cd2+ and Zn2+ is described. The fluorescent spectra changes observed upon addition of various metal ions show that 8 is highly selective for Cd2+ and Zn2+ over other metal ions. Addition of Cd2+ and Zn2+ to the solution of 8 results in ratiometric measurement. [ABSTRACT FROM AUTHOR]