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Updated: May 13, 2025
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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
10.3K
Chlorocyclohexane Valence and Rydberg Electronic Excitations
E Bandeira1, S Kumar2,3, A S Barbosa1
1Departamento de Física, Universidade Federal do Paraná, Caixa Postal 19044, Curitiba, Paraná 81531-980, Brazil.
The Journal of Physical Chemistry. A
|April 16, 2025
Summary
New measurements of chlorocyclohexane photoabsorption reveal its atmospheric behavior. Solar photolysis is a significant sink only above 20 km, impacting atmospheric chemistry models.
Area of Science:
- Atmospheric Chemistry
- Photophysics
- Quantum Chemistry
Background:
- Chlorocyclohexane (C6H11Cl) is a molecule of interest in atmospheric studies.
- Understanding its photoabsorption cross-sections is crucial for atmospheric fate assessments.
Purpose of the Study:
- To determine new cross-section values for chlorocyclohexane photoabsorption.
- To interpret the photoabsorption spectrum using theoretical calculations.
- To estimate photolysis lifetimes and assess its role as an atmospheric sink.
Main Methods:
- Vacuum ultraviolet (VUV) photoabsorption measurements (5.0-10.8 eV).
- Theoretical calculations using time-dependent density functional theory (TD-DFT).
- Assignment of excited states and spectral features.
Main Results:
- New cross-section values for C6H11Cl were obtained.
- Excited states were assigned to valence, mixed valence-Rydberg, and Rydberg transitions.
- Specific vibrational modes were linked to spectral features.
- Photolysis lifetimes indicate solar photolysis is a relevant sink only above 20 km altitude.
Conclusions:
- The study provides critical data for atmospheric modeling of chlorocyclohexane.
- Predissociative character plays a significant role in the molecule's electronic states.
- Solar photolysis is a minor sink for chlorocyclohexane in the lower atmosphere.
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