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Angular distribution of photoelectrons in small molecules: a molecular quantum defect calculation
M V Vega1, C Lavín, A M Velasco
1Departamento de Química Física y Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid, E-47005 Valladolid, Spain.
The Journal of Chemical Physics
|June 16, 2012
Summary
The molecular quantum defect orbital (MQDO) method accurately calculates photoelectron angular distributions from molecular photoionization. This study validates the MQDO method for various molecules, showing good agreement with experimental and theoretical data.
Area of Science:
- Quantum Chemistry
- Molecular Physics
- Spectroscopy
Background:
- The molecular quantum defect orbital (MQDO) method has been established for calculating photoionization cross sections.
- Understanding photoelectron angular distributions is crucial for characterizing molecular photoionization dynamics.
Purpose of the Study:
- To apply the MQDO method for calculating photoelectron angular distributions in molecular photoionization.
- To investigate the energy dependence of these distributions for several small molecules.
Main Methods:
- Utilized the MQDO method to compute angular distribution parameters.
- Performed calculations for ionization from outer valence orbitals of HF, H(2)O, NH(3), N(2)O, and H(2)CO.
- Analyzed results across a photoelectron energy range from threshold to 120 eV.
Main Results:
- Presented profiles of the angular distribution parameter as a function of photoelectron energy for the studied molecules.
- MQDO calculations demonstrated good agreement with existing experimental measurements.
- The energy dependence predicted by MQDO aligned well with more advanced theoretical models and experimental observations.
Conclusions:
- The MQDO method is a reliable tool for predicting photoelectron angular distributions in molecular photoionization.
- The study confirms the applicability of MQDO across a range of small molecules and energies.
- MQDO provides a valuable and accurate approach for theoretical investigations in molecular photoionization.
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