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Limits on the asymmetry parameters for two- and three-photon photofragmentation
1Physical and Theoretical Chemistry Laboratory, Chemistry Department, University of Oxford, South Parks Rd, Oxford, UK OX1 3QZ.
Physical Chemistry Chemical Physics : PCCP
|October 11, 2008
Summary
The asymmetry parameter constraint for single-photon fragmentation is extended to two- and three-photon processes. This research details the angular distributions and parameter regions for these multi-photon fragmentation events.
Area of Science:
- Molecular Physics
- Quantum Chemistry
- Laser Spectroscopy
Background:
- Single-photon photofragmentation has a known constraint on its asymmetry parameter (-1 <= beta <= 2).
- Understanding multi-photon fragmentation is crucial for advanced molecular studies.
Purpose of the Study:
- To generalize the asymmetry parameter constraint to two-photon and three-photon fragmentation processes.
- To characterize the angular distributions and accessible parameter spaces for these multi-photon events.
Main Methods:
- Theoretical analysis of angular distributions in two-photon fragmentation under different laser field symmetries (cylindrical and crossed linear polarizations).
- Extension of the analysis to axially symmetric three-photon fields.
- Determination of physically accessible regions within the parameter planes.
Main Results:
- The angular distribution for two-photon fragmentation is shown to be dependent on two independent parameters.
- Physically accessible regions for these parameters were established.
- The study discusses the forms of angular distributions at specific points and compares them with existing predictions.
Conclusions:
- The study successfully generalizes the asymmetry parameter constraint to multi-photon photofragmentation.
- Provides a theoretical framework for understanding and predicting angular distributions in complex molecular fragmentation scenarios.
- Offers insights for experimental design and interpretation in laser-induced molecular dynamics.
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