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Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Time-dependent alignment of molecules trapped in octahedral crystal fields
Toni Kiljunen1, Burkhard Schmidt, Nikolaus Schwentner
1Department of Chemistry, P.O. Box 35, FIN-40014 University of Jyväskylä, Finland. toni.kiljunen@jyu.fi
The Journal of Chemical Physics
|May 6, 2006
Summary
Computational study reveals how laser fields control molecular alignment in crystal fields. Results show persistent interference patterns and propose applications in crystal field interrogation and molecular dynamics control.
Area of Science:
- Physical Chemistry
- Molecular Physics
- Solid-State Physics
Background:
- Molecules confined in crystal fields exhibit hindered rotational states.
- Laser fields can induce time-dependent alignment of molecules.
Purpose of the Study:
- To computationally study molecular alignment in octahedral crystal fields using pulsed laser fields.
- To investigate the control over molecular axis direction via rotational wave packet evolution.
Main Methods:
- Computational analysis of molecular rotational states in cubic crystal fields.
- Simulation of time-dependent alignment using pulsed nonresonant laser fields.
- Investigation across ultrashort (nonadiabatic) and long (adiabatic) pulse duration regimes.
Main Results:
- Alignment degree depends on the interplay between laser field and crystal field direction (cooperative vs. competitive).
- Irregular crystal field energies cause persistent interference patterns in alignment signals.
- Nonadiabatic dynamics reveal complex alignment behaviors, contrasting with adiabatic following.
Conclusions:
- Nonadiabatic alignment can interrogate crystal-field energetics.
- Adiabatic alignment offers directional control of molecular dynamics in solids.
- Findings contrast with gas-phase molecular dynamics studies.
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