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arXiv · 0903.4463

A combined experimental and theoretical study on realizing and using laser controlled torsion of molecules

C. B. Madsen·L. B. Madsen·S. S. Viftrup·M. P. Johansson·T. B. Poulsen·L. Holmegaard·V. Kumarappan·K. A. Jorgensen·H. Stapelfeldt
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Abstract

It is demonstrated that strong laser pulses can introduce torsional motion in the axially chiral molecule 3,5-diflouro-3',5'-dibromo-biphenyl (DFDBrBPh). A nanosecond laser pulse spatially aligns the stereogenic carbon-carbon (C-C) bond axis allowing a perpendicularly polarized, intense femtosecond pulse to initiate torsional motion accompanied by a rotation about the fixed axis. We monitor the induced motion by femtosecond time-resolved Coulomb explosion imaging. Our theoretical analysis corroborates the experimental findings and on the basis of these results we discuss future applications of laser induced torsion, viz., time-resolved studies of de-racemization and laser controlled molecular junctions based on molecules with torsion.

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C. B. Madsen, L. B. Madsen, S. S. Viftrup, M. P. Johansson, T. B. Poulsen, L. Holmegaard, V. Kumarappan, K. A. Jorgensen, H. Stapelfeldt. 2009-03-25. A combined experimental and theoretical study on realizing and using laser controlled torsion of molecules. https://doi.org/10.1063/1.3149789

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