Force-spectrum relations for molecular optical force probes.

Area of Science:

• Molecular Biophysics
• Spectroscopy
• Computational Chemistry

Background:

• Force probes are essential for real-time monitoring of forces in large molecules, crucial for understanding mechanochemical reactivity and macromolecular structural changes like folding.
• Current force probe systems often rely on mechanochromism, involving changes in UV/Vis absorption spectra under mechanical stress.

Purpose of the Study:

• To propose and computationally validate a novel molecular force probe strategy utilizing reduced point-group symmetry upon mechanical deformation.
• To demonstrate the characteristic spectral changes (UV/Vis, IR, Raman) resulting from this symmetry reduction.

Main Methods:

• Computational methods were employed to simulate and predict the spectral responses of molecules undergoing mechanical deformation.
• The study focused on analyzing changes in UV/Vis, IR, and Raman spectra due to altered point-group symmetry.

Main Results:

• Mechanical deformation leading to reduced point-group symmetry induces significant and characteristic changes in UV/Vis, IR, and Raman spectra.
• These spectral alterations are reversible, indicating the potential for dynamic monitoring.
• The proposed probes are sensitive to even small applied forces.

Conclusions:

• Molecular force probes based on symmetry reduction offer a sensitive and reversible method for detecting mechanical forces in macromolecules.
• This approach provides a new avenue for investigating mechanochemical processes and structural dynamics in biological and synthetic systems.
• Computational validation supports the feasibility and potential advantages of this novel force sensing strategy.