6533b7d1fe1ef96bd125c13c
RESEARCH PRODUCT
Polyamine Linear Chains Bearing Two Identical Terminal Aromatic Units. Evidence for a Photo Induced Bending Movement
José M. LlinaresM. Alexandra BernardoM. Teresa AlbeldaConxa SorianoSérgio AlvesJ. Sérgio Seixas De MeloEnrique García-españaFernando PinaSantiago V. Luissubject
Aqueous solutionChemistryExcited stateMoleculeProtonationGeneral ChemistryTime-resolved spectroscopyExcimerPhotochemistryGround stateFluorescencedescription
Abstract Several chemosensors bearing a fluorescent unit at both ends of a linear polyamine chain were synthesised. The protonation as well as the association constants with Cu2+ and Zn2+ were determined by potentiometry in 0.15 mol dm−3 NaCl at 298.1 K. In the case of 1,16-bis(1-naphthylmethyl)-1,4,7,10,13,16-hexaazadecane hexahydrochloride (L1), formation of an excimer emission in aqueous acidic solutions was observed. The system was characterized by steady state fluorescence emission and by time resolved fluorescence. In the ground state the molecule is expected to adopt a more or less linear conformation, while in the excited state a bending movement of the chain must occur in order to allow the excimer emission. The system can be viewed as an elementary machine driven by light.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2001-05-01 | Supramolecular Chemistry |