SURFACE ELECTRONIC STATES OF ADSORBED NITROGEN MOLECULES ON OXIDIZED NICKEL SURFACE

We present a new technique to investigate the electronic surface struc tures of metal electrodes and experimental data on oxidized surfaces o f nickel electrodes. The experimental system consists of a simple trio de structure and an electromagnet to control the momentum of incident electrons. The magnetic field dependence of the transmission electron current to the metal electrodes depends on the electron density at the electrode surface. When the electron density at the surface is high, the incident electrons are scattered by quantized surface states in th e surface potential barrier. On the other hand, in the case of low ele ctron density, the incident electrons show resonance characteristics d ue to the presence of discrete electronic states as a result of the ge neration of a periodic surface potential. Molecular nitrogen adsorptio n causes a change in the surface potential, and the bonding states int ermediate between covalent bonds and van der Waal's-like bonds are det ected.