Negative ions of nitroethane and its clusters.

Area of Science:

• Physical Chemistry
• Chemical Physics
• Quantum Chemistry

Background:

• Nitroethane (NE) and its clusters can form dipole-bound and valence-bound negative ions.
• Understanding these anion states is crucial for molecular interactions and reaction dynamics.

Purpose of the Study:

• To characterize the electronic properties of nitroethane anions and their clusters.
• To investigate the role of dipole-bound states as "doorway states" to valence-bound anions.
• To compare experimental findings with theoretical calculations.

Main Methods:

• Photoelectron Spectroscopy (PES) to measure adiabatic electron affinities.
• Rydberg Electron Transfer (RET) techniques to probe anion states.
• Ab initio calculations for theoretical validation and visualization.

Main Results:

• Adiabatic electron affinities of NE clusters increase with size (0.3 eV for n=1 to 2.1 eV for n=5).
• Vertical detachment energies were also measured for NE clusters.
• RET experiments suggest dipole-bound states act as doorways to valence-bound states, with unique n(*) and [l] dependencies observed.

Conclusions:

• Nitroethane clusters form anions where the excess electron localizes on a single monomer.
• The study provides a detailed understanding of electron binding in NE anions.
• Experimental and theoretical results show good agreement, enhancing confidence in the findings.