Electron binding energies in dipole-bound anions
- Pacific Northwest National Lab., Richland, WA (United States)
- Univ. of Utah, Salt Lake City, UT (United States)
- Univ. of Gdansk (Poland)
- Univ. of Pittsburgh, PA (United States)
Dipole-bound anionic states of polar molecules (HCN, CH{sub 3}CN, C{sub 3}H{sub 2}, C{sub 4}, H{sub 2}, C{sub 5} H{sub 2}(H{sub 2}O){sub 2} (HF){sub 2}, and (HCN){sub 2}) were studied using high-level correlated electronic structure methods. It is demonstrated that the total electron correlation contribution to the stability of the anions encompasses two physically distinct effects: (i) dynamical correlation between the loosely bound electron and the electrons of the neutral molecule, and (ii) the change in the binding energy due to improved description of the molecular dipole moment. The former effect, which may be compared with the dispersion interaction in van-der-Waals systems, represents a large fraction of the total binding energy. Geometry relaxation of the molecular framework upon electron attachment and differences in zero-point vibrational energies between the dipole-bound anion and the neutral molecule proved to be important for polar dimers. The predicted values of the electron affinities of the dipole bound states of CH{sub 3}CN and C{sub 3}H{sub 2}, 108 and 173 cm{sup -1}, respectively, are in excellent agreement with the recent experimental results 93 cm{sup -1} and 171 {+-} 50 cm{sup -1}.
- DOE Contract Number:
- AC06-76RL01830
- OSTI ID:
- 447556
- Report Number(s):
- CONF-960343--
- Country of Publication:
- United States
- Language:
- English
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