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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Formation of coherent rotational wavepackets in small molecule-helium clusters using impulsive alignment
Gediminas Galinis1, Luis G Mendoza Luna, Mark J Watkins
1University of Leicester, Department of Physics & Astronomy, Leicester, LE1 7RH, UK. kvh6@le.ac.uk.
Abstract:
We show that rotational line spectra of molecular clusters with near zero permanent dipole moments can be observed using impulsive alignment. Aligned rotational wavepackets were generated by non-resonant interaction with intense femtosecond laser pump pulses and then probed using Coulomb explosion by a second, time-delayed femtosecond laser pulse. By means of a Fourier transform a rich spectrum of rotational eigenstates was derived. For the smallest cluster, C(2)H(2)-He, we were able to establish essentially all rotational eigenstates up to the dissociation threshold on the basis of theoretical level predictions. The C(2)H(2)-He complex is found to exhibit distinct features of large amplitude motion and very early onset of free internal rotor energy level structure.
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