Resonance processes ejection

Franzen, J. The nonlinear ion-trap 5. Nature of nonlinear resonances and resonant ion ejection. Int. J. Mass Spectrom. Ion Processes 1994,130,15 0. 

If the work function is smaller than the ionization potential of metastable state (see. Fig. 5.18b), then the process of resonance ionization becomes impossible and the major way of de-excitation is a direct Auger-deactivation process similar to the Penning Effect ionization a valence electron of metal moves to an unoccupied orbital of the atom ground state, and the excited electron from a higher orbital of the atom is ejected into the gaseous phase. The energy spectrum of secondary electrons is characterized by a marked maximum corresponding to the... 

The physical process of resonance neutron scattering is through the formation of a compound nucleus . Cd, and Gd belong to the small class of nuclei which exhibit a resonance in the thermal energy region. In the case of Cd the compound nucleus Cd will either eject a neutron in an (n, n) process or emit y-rays in an (n, y) process the latter being inelastic. Unlike in X-ray anomalous dispersion, in the present case both the elastic (n, n) and inelastic (n, y) processes contribute to b"(0) ... 

An alternative mechanism to resonant neutralization is Auger neutralization. The latter process involves a two-electron reorganization whereby one electron from the solid tunnels across to the ion while a second electron is excited out of the conduction band of the metal. If the second electron has sufficient energy, it may be ejected from the surface and is referred to as an Auger electron. 

Electronic Feshbach resonances are often very long lived and hence have narrow (often < 0.01 eV) widths. Their lifetimes are determined by the coupling between the quasibound and asymptotic components of their electronic wavefunctions. Because the Feshbach decay process Involves ejection of one electron and deexcltatlon of a second, It proceeds via the two-electron terms e /r.. In the Hamiltonian. For example, the rate of electron loss lil H (2s2p, P°) Is proportional to the square of the two-electron Integral <2s2p(e /r.21 Is kp>, where kp represents the continuum p-wave orbital. This Integral, and hence the decay rate. Is often quite small because of the size difference between the 2s or 2p and Is orbitals and because of the oscillatory nature of the kp orbital. 

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