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pradajose
Jul12-03, 08:42 AM
.- Does anybody know a reference for an intuitive model of the work function?
If not, is there a simple quantum mechanical model for it?

.- Does anybody know of a simple model for a solid - electrolite interface?.

.- What about a metal - metal interface?.

.- I'm looking for an intuitive or mechanistic model of electron displacement (transport) at the interface of two metals in orden to explain potential diferences between them.

Tyger
Jul12-03, 07:08 PM
that my help you some.

The work function is just the total binding energy for a conduction electron in a metal crystal. Let's compare the crystal to one metal atom. The conduction electrons are more spread out and have lower wavenumber (momentum) than the single atom, and as such have lower kinetic energy, so they are bound more tightly. They also typically have lower potential energy too. So they can have higher binding energies that the 13ev typical for an atom.

One interesting application where the work function is used to advantage is in gas discharge voltage regulators. You have a metal/noble-gas interface. Approx. 12 volts is dropped as ionization voltage across the gas, the remaining 50 to 140 volts is dropped across the metal work function. The electons actually tunnel through the work function potential barrier, representing perhaps the first appplication of QM tunneling that was recognized.

Gas discharge devices are well studied and have an extensive literature.