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Quadrupole-bound anions are negative ions in which their excess electrons are loosely bound by long-range electron-quadrupole attractions. Experimental evidence for quadrupole-bound anions has been scarce; until now, only trans -succinonitrile had been experimentally confirmed to form a quadrupole-bound anion. In this study, we present experimental evidence for a new quadrupole-bound anion. Our combined Rydberg electron transfer/anion photoelectron spectroscopy study demonstrates that the ee conformer of 1,4-dicyanocyclohexane (DCCH) supports a quadrupole-bound anion state, and that the cis -DCCH conformer forms a dipole-bound anion state. The electron binding energies of the quadrupole- and dipole-bound anions are measured as 18 and 115 meV, respectively, both of which are in excellent agreement with theoretical calculations by Sommerfeld.
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Excess electrons bound to H 2 S trimer and tetramer clusters
We have prepared the hydrogen sulfide trimer and tetramer anions, (H 2 S) 3 − and (H 2 S) 4 − , measured their anion photoelectron spectra, and applied high-level quantum chemical calculations to interpret the results. The sharp peaks at low electron binding energies in their photoelectron spectra and their diffuse Dyson orbitals are evidence for them both being dipole-bound anions. While the dipole moments of the neutral (H 2 S) 3 and (H 2 S) 4 clusters are small, the excess electron induces structural distortions that enhance the charge-dipolar attraction and facilitate the binding of diffuse electrons.
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- Award ID(s):
- 1664182
- PAR ID:
- 10168042
- Date Published:
- Journal Name:
- Physical Chemistry Chemical Physics
- Volume:
- 22
- Issue:
- 6
- ISSN:
- 1463-9076
- Page Range / eLocation ID:
- 3273 to 3280
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c9cp06872d
