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Concept# Free electron model

Summary

In solid-state physics, the free electron model is a quantum mechanical model for the behaviour of charge carriers in a metallic solid. It was developed in 1927, principally by Arnold Sommerfeld, who combined the classical Drude model with quantum mechanical Fermi–Dirac statistics and hence it is also known as the Drude–Sommerfeld model.
Given its simplicity, it is surprisingly successful in explaining many experimental phenomena, especially

- the Wiedemann–Franz law which relates electrical conductivity and thermal conductivity;
- the temperature dependence of the electron heat capacity;
- the shape of the electronic density of states;
- the range of binding energy values;
- electrical conductivities;
- the Seebeck coefficient of the thermoelectric effect;
- thermal electron emission and field electron emission from bulk metals.

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