High resolution low-energy electron attachment to molecular clusters of sulfur dioxide

Vibrational Autodetachment from Anionic Nitroalkane Chains: From Molecular Signatures to Thermionic Emission

“…While the Wigner threshold law does not hold strictly for the electron-dipole potential (∝ 1/ r 2 ), this potential decays faster than the attractive Coulomb potential (∝ 1/ r ), where the capture cross section is proportional to 1/ E . As proposed by Klots and shown experimentally by Hotop and co-workers, − the capture cross section for many molecules can be described with a behavior between Wigner’s threshold law for s -wave capture (∝ 1/ E 1/2 ) and the behavior for attractive Coulomb potentials (∝ 1/ E ).…”

“…For most molecules, electron attachment at low energies is predominantly an s -wave process, so . However, this limiting behavior is strictly only correct at threshold, and the attachment cross section is often observed to fall off more rapidly at energies as low as 1 meV, also in the absence of a permanent dipole moment. − …”

“…In the context of an empirical model based on limiting behavior between short-range s -wave capture and Coulomb capture as discussed above, the other limiting case would be γ = 0 for a 1/ E dependence of the cross section. Hotop and co-workers have used a similar expression to describe low-energy electron attachment. − …”

Long-range effects in electron scattering by polar molecules

“…The simple potential-well plus polarization tail model [153,154] is able to describe the dependence of the resonance position on the number of units N: with the growth of N the resonances are red-shifted because of the increase of the binding energy. Very pronounced VFRs were observed in electron attachment to N 2 O [22,154], CO 2 [153,163], OCS [164], and SO 2 [162] clusters. The theory outlined above was used for description of electron attachment to CO 2 , N 2 O and SO 2 clusters.…”

“…This approach allowed a description of important experimentally observed features: cusps in elastic electron scattering and VE of SF 6 [158] and VFRs in electron attachment to CO 2 [159] and SO 2 [162] clusters. These resonances are formed by electron capture into the polarization potential of the cluster with a simultaneous VE of one molecular units.…”