Molecular Implementation of Sequential and Reversible Logic Through Photochromic Energy Transfer Switching
Journal article, 2011

Photochromic spiropyrans modified with fluorophores were investigated as molecular platforms for the achievement of fluorescence switching through modulation of energy transfer. The dyads were designed in such a way that energy transfer is only observed for the open forms of the photochrome (merocyanine and protonated merocyanine), whereas the closed spiropyran is inactive as an energy acceptor. This was made possible through a deliberate choice of fluorophores (4-amino-1,8-naphthalimide, dansyl, and perylene) that produce zero spectral overlap with the spiro form and considerable overlap for the merocyanine forms. From the Förster theory, energy transfer is predicted to be highly efficient and in some cases of 100 % efficiency. The combined switching by photonic (light of λ>530 nm) and chemical (base) inputs enabled the creation of a sequential logic device, which is the basic element of a keypad lock. Furthermore, in combination with an anthracene-based acidochromic fluorescence switch, a reversible logic device was designed. This enables the unambiguous coding of different input combinations through multicolour fluorescence signalling. All devices can be conveniently reset to their initial states and repeatedly cycled.

energy transfer

spiro compounds


logic gates



Patricia Remón Ruiz

University of Huelva

Martin Hammarson

Chalmers, Chemical and Biological Engineering, Physical Chemistry

Shiming Li

Chalmers, Chemical and Biological Engineering, Physical Chemistry

Axel Kahnt

Chalmers, Chemical and Biological Engineering, Physical Chemistry

U. Pischel

University of Huelva

Joakim Andreasson

Chalmers, Chemical and Biological Engineering, Physical Chemistry

Chemistry - A European Journal

0947-6539 (ISSN) 1521-3765 (eISSN)

Vol. 17 23 6492-6500

Photochromic Systems for Solid State Molecular Electronic Devices and Light-Activated Cancer Drugs (PHOTOCHROMES)

European Commission (EC) (EC/FP7/203952), 2008-09-01 -- 2013-08-31.

Areas of Advance

Nanoscience and Nanotechnology

Subject Categories

Physical Chemistry



More information

Latest update

3/2/2022 3