Correlation-bound anions of NaCl clusters.
Thomas Sommerfeld1, Bijay Bhattarai, Victor P Vysotskiy
1Department of Chemistry and Physics, Southeastern Louisiana University, SLU 10878, Hammond, Louisiana 70402, USA. thomas.sommerfeld@selu.edu
The Journal of Chemical Physics
|September 28, 2010
Summary
Researchers discovered a new type of sodium chloride cluster anion, (NaCl)(N)(-), that requires electron correlation for binding. This finding challenges previous models and suggests cluster abundance in experiments may not reflect stability.
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Materials Science
Background:
- Previous studies identified various electron binding motifs in sodium chloride cluster anions.
- Excess electron binding was primarily explained by one-electron potentials due to neutral cluster multipole moments.
Purpose of the Study:
- Investigate a novel class of (NaCl)(N)(-) anions bound via electron correlation.
- Characterize correlation-bound states in trimers and tetramers.
- Compare these states with known binding mechanisms.
Main Methods:
- Green's function method
- Equation-of-motion coupled-cluster (CC) method
- Analysis of electron binding energies and natural orbitals
Main Results:
- Identified correlation-bound states for (NaCl)(3)(-) and (NaCl)(4)(-).
- The correlation-bound state is the most stable isomer for (NaCl)(4)(-).
- Computed binding energies and electron distributions differ from dipole-bound, quadrupole-bound, and defectlike anions.
Conclusions:
- Electron correlation is crucial for certain alkali halide cluster anions.
- Results offer a test for improved one-electron model potentials.
- Cluster abundance in photoelectron spectra may not correlate with relative stability.
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