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Title: Molecular bond stabilization in the strong-field dissociation of O2+
We theoretically examine the rotational and vibrational dynamics of O2+ molecular ions exposed to intense, short laser pulses for conditions realized in contemporary pump-probe experiments.We solve the time-dependent Schrödinger equation within the Born-Oppenheimer approximation for an initial distribution of randomly aligned molecular ions. For fixed peak intensities, our numerical results show that total, angle-integrated O2+ → O(3P) + O+(4S0 ) dissociation yields do not monotonically increase with increasing infrared-probe pulse duration. We find this pulse-duration-dependent stabilization to be consistent with the transient trapping of nuclear probability density in a light-induced (bond-hardening) potential-energy surface and robust against rotational excitation. We analyze this stabilization effect and its underlying bond-hardening mechanism (i) in the time domain, by following the evolution of partial nuclear probability densities associated with the dipole-coupled O2+(a 4Pi u ) and O2+( f 4 Pi g) cationic states, and (ii) in the frequency domain, by examining rovibrational quantum-beat spectra for the evolution of the partial nuclear probability densities associated with these states. Our analysis reveals the characteristic timescale for the bond-hardening mechanism in O2+ and explains the onset of bond stabilization for sufficiently long pulse durations.  more » « less
Award ID(s):
1802085
PAR ID:
10168259
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Physical review and Physical review letters index
Volume:
101
ISSN:
0094-0003
Page Range / eLocation ID:
043410
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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