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Transient two-dimensional vibrational spectroscopy of an operating molecular machine
Matthijs R Panman1,2, Chris N van Dijk3, Adriana Huerta-Viga3,4
1Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands. matthijs.panman@gu.se.
Nature Communications
|December 22, 2017
Summary
Researchers used transient two-dimensional infrared (T2DIR) spectroscopy to observe molecular machine conformational changes. This technique revealed a macrocycle adopting a boat-like shape at its final station, unlike its initial chair-like form.
Area of Science:
- Molecular nanotechnology
- Chemical physics
- Spectroscopy
Background:
- Synthetic molecular machines are key for future nanodevices.
- Understanding their mechanical behavior is crucial for nanodevice design.
- Current knowledge of molecular-level mechanics is limited.
Purpose of the Study:
- To monitor conformational changes in a translational molecular machine during operation.
- To demonstrate the utility of transient two-dimensional infrared (T2DIR) spectroscopy for this purpose.
- To develop a method for simplifying complex T2DIR spectra.
Main Methods:
- Utilized transient two-dimensional infrared (T2DIR) spectroscopy.
- Initiated molecular machine translation using a UV pulse.
- Employed a subtraction method to reduce spectral congestion.
- Analyzed spectral changes to identify conformational shifts.
Main Results:
- Successfully monitored conformational changes of a translational molecular machine.
- Observed the arrival of the shuttling macrocycle at the final station via a new cross peak.
- Determined that the macrocycle adopts a boat-like conformation at the final station.
- Confirmed a chair-like conformation at the initial station.
Conclusions:
- Transient two-dimensional infrared (T2DIR) spectroscopy is effective for tracking molecular machine dynamics.
- The study elucidates the conformational changes occurring during molecular machine operation.
- The subtraction method enhances the applicability of T2DIR spectroscopy to complex systems.
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