https://doi.org/10.1007/s100530050124
Electrons weakly bound to molecules by dipolar, quadrupolar or polarization forces
Laboratoire de Physique des Lasers, Institut Galilée,
Université Paris-Nord, 93430 Villetaneuse, France
Corresponding author: a desfranc@lpl.univ-paris13.fr
Received:
11
December
1997
Revised:
13
March
1998
Accepted:
18
March
1998
Published online: 15 May 1998
Within the framework of a simple electrostatic model we here discuss the stability of very weakly bound molecular negative ions. In contrast with the case of conventional valence anions, the excess electron is then located in a very diffuse orbital and is mainly bound by electrostatic dipolar, quadrupolar and polarization forces at large distances from the neutral molecular core. By fitting a single repulsion parameter of the model to the available experimental data, it is possible to make quantitative predictions of the excess electron binding energies in these species. Critical values of dipole moment, quadrupole moment or polarizability required for the observation of stable dipole-bound, quadrupole-bound or polarization-bound negative ions are predicted.
PACS: 34.50.Gb – Electronic excitation and ionization of molecules; intermediate molecular states (including lifetimes, state mixing, etc.) / 36.90.+f – Other special atoms, molecules, ions, and clusters
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1998
