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Updated: Jun 20, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Selective infrared excitation in D2CO: rotational assignments and the role of collisions
1School of Chemistry, The University of New South Wales, Sydney, NSW 2033, Australia.
Abstract:
A time-resolved infrared-ultraviolet double-resonance technique is used to characterize specific rovibrational states pumped by a pulsed CO(2) laser within the nu(4) vibrational ladder of D(2)CO. The roles of rotational and quasiresonant rovibrational relaxation, requiring, respectively, < or =1 and approximately 3 gas-kinetic collisions, are studied. The rotational specificity of the latter suggests that a collision-assisted sequence of infrared absorption steps is able to account for the selective initial stages of multiple-photon excitation in formaldehyde.
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