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  • Charge Migration in HCCI Cations Probed by Strong Field Ionization: Time-Dependent Configuration Interaction and Vibrational Wavepacket Simulations
Title: Charge Migration in HCCI Cations Probed by Strong Field Ionization: Time-Dependent Configuration Interaction and Vibrational Wavepacket Simulations
Strong field ionization of neutral iodoacetylene (HCCI) can produce a coherent superposition of the X and A cations and results in charge migration between the CC  orbital and the iodine -type lone pair. This charge migration causes oscillations in the rate of strong field ionization of the cation to the dication that can be monitored using intense, few cycle probe pulses. The dynamics and strong field ionization of the coherent superposition the X and A states of HCCI+ have been modelled by time dependent configuration interaction simulations. When the nuclei are allowed to move, the electronic wavefunctions need to be multiplied by vibrational wavefunctions. Nuclear motion has been modelled by vibrational packets moving on quadratic approximations to the potential energy surfaces for the X and A states of the cation. The overlap of the vibrational wavepackets decays in about 10-15 fs. Consequently, the oscillations in the strong field ionization decay on the same time scale. A revival of the vibrational overlap and in the oscillations of the strong field ionization is seen at 60 – 110 fs. TDCI simulations show that the decay and revival of the charge migration can be monitored by strong field ionization with intense 2 and 4 cycle linearly polarized 800 nm pulses. The revival is also seen with 7 cycle pulses.  more » « less
Award ID(s):
1856437
PAR ID:
10500147
Author(s) / Creator(s):
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
The Journal of Physical Chemistry A
Volume:
127
Issue:
29
ISSN:
1089-5639
Page Range / eLocation ID:
6040 to 6050
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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