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Updated: Jun 16, 2026
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Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
Unraveling Solvent-Independent Excited State Proton Transfer Dynamics in Sterically Substituted Photoactive Systems.
Zofia Majewska1, Jacob Eller2, Kexin Pan1
1School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
The Journal of Physical Chemistry Letters
|June 13, 2026
Summary
Excited state proton transfer (ESPT) in complex molecules like BEMT and MBBT is largely independent of solvent polarity. Intrinsic electronic properties, not just bulky groups, drive this solvent-invariant behavior, guiding future photoactive system design.
Area of Science:
- Photochemistry
- Molecular Dynamics
- Materials Science
Background:
- Excited state proton transfer (ESPT) is crucial for photoactive molecules but sensitive to environmental polarity.
- Complex triazine and benzotriazole derivatives are key photoactive systems.
Purpose of the Study:
- Investigate the excited state photodynamics of BEMT and MBBT.
- Determine the influence of solvent polarity on intramolecular ESPT.
- Elucidate the role of bulky substituents in ESPT dynamics.
Main Methods:
- Femtosecond transient electronic absorption spectroscopy in various solvents.
- Mixed-reference spin-flip time-dependent density functional theory (TD-DFT) calculations.
Main Results:
- Ultrafast relaxation in BEMT and MBBT is governed by solvent-insensitive intramolecular ESPT.
- Solvent independence arises from intrinsic electronic properties, not steric bulk.
- Bulky substituents enhance solvent-invariant ESPT dynamics.
Conclusions:
- BEMT and MBBT exhibit efficient intramolecular ESPT largely unaffected by solvent polarity.
- Intrinsic electronic factors are primary drivers of solvent-invariant ESPT.
- Design principles for next-generation photoactive systems can leverage these findings.
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