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09:09
Targeted Studies Using Serial Block Face and Focused Ion Beam Scan Electron Microscopy
Published on: August 10, 2019
Crossed-beam studies of electron transfer to oriented trichloronitromethane, CCl(3)NO(2), molecules
Peter W Harland1, Philip R Brooks
1Department of Chemistry and Rice Quantum Institute, Rice University, Houston, Texas 77251, USA.
The Journal of Chemical Physics
|February 2, 2010
Summary
Fast potassium atoms react with trichloronitromethane (CCl(3)NO(2)) to form various ions. Electron affinities and bond strengths were determined, revealing weaker C-N and N-O bonds compared to nitromethane.
Area of Science:
- Chemical Physics
- Molecular Collisions
- Mass Spectrometry
Background:
- Understanding electron transfer reactions is crucial in chemical dynamics.
- Trichloronitromethane (CCl(3)NO(2)) is a molecule with potentially reactive bonds.
- Potassium atom collisions provide a controlled method to study molecular anions.
Purpose of the Study:
- To investigate the electron transfer process between potassium atoms and CCl(3)NO(2).
- To determine the threshold energies for ion formation and estimate electron affinities of negative ions.
- To elucidate the fragmentation pathways of CCl(3)NO(2) anions.
Main Methods:
- Collision of fast potassium atoms with oriented CCl(3)NO(2) molecules.
- Measurement of threshold energies for various negative ions (O(-), Cl(-), NO(2)(-), CCl(3)(-), CCl(2)NO(2)(-), CCl(3)NO(-), CCl(3)NO(2)(-)).
- Estimation of electron affinities for specific fragment anions.
Main Results:
- Formation of multiple negative ions including parent anion CCl(3)NO(2)(-).
- Electron affinities for CCl(2)NO(2)(-), CCl(3)NO(-), and CCl(3)NO(2)(-) estimated at 2.35, 2.35, and 1.89 eV, respectively.
- Threshold energies indicate weaker C-N and N-O bonds in CCl(3)NO(2) compared to nitromethane.
Conclusions:
- Electron transfer to the pi(*)(NO) orbital is a primary pathway at lower energies.
- The parent negative ion CCl(3)NO(2)(-) is stabilized by K(+) interaction.
- Fragmentation pathways are influenced by collision energy and molecular orientation, providing insights into bond dissociation.
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