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Updated: Jun 19, 2026
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Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Lattice-Directed Spin-Vibronic Coherence-Mediated Ultrafast Intersystem Crossing in Crystalline Diplatinum Complex.
Nita Ghosh1, Julien Eng2, Sarah Kromer3
1Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON M5S3H6, Canada.
Journal of the American Chemical Society
|June 17, 2026
Summary
Researchers discovered ultrafast spin-vibronic-mediated intersystem crossing (ISC) in platinum crystals, showing a tenfold increase in ISC rates due to lattice effects. This finding offers new ways to control chemical reactions at the molecular level.
Area of Science:
- Chemical Physics
- Materials Science
- Photochemistry
Background:
- Controlling chemical reactivity at the molecular level requires understanding environmental interactions.
- Reactivity in single crystals is influenced by lattice packing and electrostatic potentials, differing from solution-phase behavior.
- Studying ultrafast photochemical reactions in crystals is challenging due to sample depletion and product accumulation.
Purpose of the Study:
- To investigate ultrafast spin-vibronic-mediated intersystem crossing (ISC) in single crystals of binuclear platinum complexes.
- To explore the influence of lattice effects and system-bath interactions on ISC rates.
- To establish a framework for controlling ISC dynamics through molecular structure and environment.
Main Methods:
- Ultrafast spectroscopic measurements with advanced time-frequency analysis.
- Comparative studies of structurally analogous platinum complexes.
- Quantum-dynamical calculations.
Main Results:
- First report of ultrafast spin-vibronic-mediated ISC leading to intramolecular charge transfer in single platinum crystals.
- A tenfold increase in ISC rate observed in crystals compared to solution phase, attributed to lattice-tuned energetics.
- Identification of the critical role of bath-controlled tuning of an intermediate state in facilitating efficient ISC.
Conclusions:
- Lattice effects significantly enhance ISC rates in single-crystal platinum complexes.
- System-bath interactions provide a mechanism for controlling ISC dynamics.
- A general framework for structure-guided control of ISC is established, applicable to molecular reactivity.
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