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Updated: Mar 13, 2026

Fluorescence Lifetime Imaging of Molecular Rotors in Living Cells
Published on: February 9, 2012
Excited-State Decay Pathways of Molecular Rotors: Twisted Intermediate or Conical Intersection?
Tomislav Suhina1,2, Saeed Amirjalayer3, Benedetta Mennucci4
1van 't Hoff Institute for Molecular Sciences, University of Amsterdam , P.O. Box 94157, 1090 GD Amsterdam, The Netherlands.
Abstract:
The fluorescence intensity of molecular rotors containing the dicyanomethylenedihydrofuran (DCDHF) motif increases strongly with solvent viscosity. Single-bond and double-bond rotations have been proposed as pathways of nonradiative decay for this and related molecular rotors. We show here that both are involved in the case of DCDHF rotors: Fluorescence is quenched by rotation around the dicyanomethylene double bond in nonpolar solvents, but in a sufficiently polar environment rotation about a formally single bond leads to a dark internal charge-transfer state.
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