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Control defeasance by anti-alignment in the excited state
Bo Y Chang1, Seokmin Shin, Jesús González-Vázquez
1School of Chemistry, Seoul National University, Seoul 08826, Republic of Korea.
Physical Chemistry Chemical Physics : PCCP
|October 19, 2019
Summary
Strong laser fields induce anti-alignment in excited H2+ molecules. Opposite sign polarizabilities in excited states prevent laser control, aligning molecules perpendicular to the field.
Area of Science:
- Physical Chemistry
- Quantum Mechanics
- Molecular Physics
Background:
- Strong laser fields are used to control molecular alignment.
- Homonuclear dimers like H2+ exhibit unique responses to electromagnetic fields.
- Ground state alignment relies on transition dipoles and polarizabilities.
Purpose of the Study:
- To predict anti-alignment dynamics in the excited state of H2+ and similar molecules.
- To investigate the influence of strong fields on excited state molecular behavior.
- To determine the feasibility of laser-control strategies for excited state alignment.
Main Methods:
- Theoretical prediction of molecular dynamics.
- Analysis of quantum mechanical interactions between molecules and strong fields.
- Calculation of polarizabilities and torques in excited states.
Main Results:
- Anti-alignment dynamics are predicted in the excited state of H2+.
- Excited state polarizabilities possess opposite signs compared to the ground state.
- A torque is generated, aligning the molecule perpendicular to the applied field.
Conclusions:
- Laser-control strategies for ground state alignment are ineffective for excited states.
- The inherent anti-alignment dynamics in excited states preclude external control.
- Understanding these dynamics is crucial for advanced molecular manipulation.
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