title: Photophysics of Calix[4]biscrown-based ditopic receptors of caesium containing one or two dioxocoumarin fluorophores.
abstract: The ditopic receptors Calix-COU1 and Calix-COU2 consist of a calix[4]biscrown containing one or two dioxycoumarin fluorophores, respectively, inserted into the crown. They can form 1:1 and 2:1 (metal:ligand) complexes with caesium ions. The photophysical properties of the 1:1 complexes can be explained by (i) cation tunneling through the tube-shaped cavity (composed of the four phenyl rings) of the calix[4]biscrown, (ii) photodisruption of the interaction between the bound cation and the oxygen atoms belonging to both the coumarin moiety and the crown, (iii) photoinduced motions of the cation.
authors.affiliation: CNRS UMR 8531, Laboratoire PPSM, Département de Chimie, ENS-Cachan, 61 Av. du Président Wilson, F-94235 Cachan, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Leray
authors.forename: Zouhair
authors.initials: Z
authors.lastname: Asfari
authors.forename: Jacques
authors.initials: J
authors.lastname: Vicens
authors.forename: Bernard
authors.initials: B
authors.lastname: Valeur
mesh_terms: D000465:Algorithms; D047250:Calixarenes / Q000737:chemistry*; D002586:Cesium / Q000737:chemistry*; D002614:Chelating Agents / Q000737:chemistry*; D003374:Coumarins / Q000737:chemistry*; D043844:Crown Ethers / Q000737:chemistry*; D008956:Models, Chemical; D010636:Phenols / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry
chemical_list: D002614:Chelating Agents; D003374:Coumarins; D043844:Crown Ethers; D010636:Phenols; C121325:calix(4)arene; D047250:Calixarenes; D002586:Cesium