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Title: Enhancing reactivity of SiO+ ions by controlled excitation to extreme rotational states
Abstract Optical pumping of molecules provides unique opportunities for control of chemical reactions at a wide range of rotational energies. This work reports a chemical reaction with extreme rotational excitation of a reactant and its kinetic characterization. We investigate the chemical reactivity for the hydrogen abstraction reaction SiO++ H2 → SiOH++ H in an ion trap. The SiO+cations are prepared in a narrow rotational state distribution, including super-rotor states with rotational quantum number (j) as high as 170, using a broad-band optical pumping method. We show that the super-rotor states of SiO+substantially enhance the reaction rate, a trend reproduced by complementary theoretical studies. We reveal the mechanism for the rotational enhancement of the reactivity to be a strong coupling of the SiO+rotational mode with the reaction coordinate at the transition state on the dominant dynamical pathway.  more » « less
Award ID(s):
1806861
PAR ID:
10473372
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Nature Communications
Date Published:
Journal Name:
Nature Communications
Volume:
14
Issue:
1
ISSN:
2041-1723
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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