Internal Stark effect of single-molecule fluorescence.
Kirill VasilevBenjamin DoppagneTomas NeumanAnna RosławskaHervé BulouAlex BoeglinFabrice ScheurerGuillaume SchullPublished in: Nature communications (2022)
The optical properties of chromophores can be efficiently tuned by electrostatic fields generated in their close environment, a phenomenon that plays a central role for the optimization of complex functions within living organisms where it is known as internal Stark effect (ISE). Here, we realised an ISE experiment at the lowest possible scale, by monitoring the Stark shift generated by charges confined within a single chromophore on its emission energy. To this end, a scanning tunneling microscope (STM) functioning at cryogenic temperatures is used to sequentially remove the two central protons of a free-base phthalocyanine chromophore deposited on a NaCl-covered Ag(111) surface. STM-induced fluorescence measurements reveal spectral shifts that are associated to the electrostatic field generated by the internal charges remaining in the chromophores upon deprotonation.
Keyphrases
- single molecule
- living cells
- atomic force microscopy
- molecular dynamics simulations
- photodynamic therapy
- high glucose
- optical coherence tomography
- quantum dots
- gene expression
- genome wide
- computed tomography
- gram negative
- oxidative stress
- energy transfer
- magnetic resonance
- highly efficient
- multidrug resistant
- high speed
- solid state