Description of Molecular Dynamics in Intense Laser Fields by the Time-Dependent Adiabatic State Approach: Application to Simultaneous Two-Bond Dissociation of CO2 and Its Control
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- 作者：Yukio Sato ; Hirohiko Kono ; Shiro Koseki ; and Yuichi Fujimura
- 刊名：Journal of the American Chemical Society
- 出版年：2003
- 出版时间：July 2, 2003
- 年：2003
- 卷：125
- 期：26
- 页码：8019 - 8031
- 全文大小：387K
- 年卷期：v.125,no.26(July 2, 2003)
- ISSN：1520-5126
文摘
We theoretically investigated the dynamics of structural deformations of CO2 and its cations innear-infrared intense laser fields (~1015 W cm-2) by using the time-dependent adiabatic state approach.To obtain "field-following" adiabatic potentials for nuclear dynamics, the electronic Hamiltonian includingthe interaction with the instantaneous laser electric field is diagonalized by the multiconfiguration self-consistent-field molecular orbital method. In the CO2 and CO2+ stages, ionization occurs before the fieldintensity becomes high enough to deform the molecule. In the CO22+ stage, simultaneous symmetric two-bond stretching occurs as well as one-bond stretching. Two-bond stretching is induced by an intense fieldin the lowest time-dependent adiabatic state 
1> of CO22+, and this two-bond stretching is followed by theoccurrence of a large-amplitude bending motion mainly in the second-lowest adiabatic state 2> nonadiabatically created at large internuclear distances by the field from 1>. It is concluded that the experimentallyobserved stretched and bent structure of CO23+ just before Coulomb explosions originates from the structuraldeformation of CO22+. We also show in this report that the concept of "optical-cycle-averaged potential" isuseful for designing schemes to control molecular (reaction) dynamics, such as dissociation dynamics ofCO2, in intense fields. The present approach is simple but has wide applicability for analysis and predictionof electronic and nuclear dynamics of polyatomic molecules in intense laser fields.
1> of CO22+, and this two-bond stretching is followed by theoccurrence of a large-amplitude bending motion mainly in the second-lowest adiabatic state 2> nonadiabatically created at large internuclear distances by the field from 1>. It is concluded that the experimentallyobserved stretched and bent structure of CO23+ just before Coulomb explosions originates from the structuraldeformation of CO22+. We also show in this report that the concept of "optical-cycle-averaged potential" isuseful for designing schemes to control molecular (reaction) dynamics, such as dissociation dynamics ofCO2, in intense fields. The present approach is simple but has wide applicability for analysis and predictionof electronic and nuclear dynamics of polyatomic molecules in intense laser fields.