|
In physics, the free electron model is a simple model for the behaviour of electrons in a crystal structure of a metallic solid. Developed principally by Drude and Sommerfeld, the free electron model neglects not only the Coulomb interaction between electrons, but also the interaction between the electrons and the atomic lattice through which they move. The free electron model is a quantum model as opposed to the Drude model, which is classical. Once the effects of quantum mechanics are taken into account, many of the experimental predictions of the model are surprisingly accurate, given its simplicity. The free electron model should be contrasted with the tight-binding model, which uses the opposite simplification of treating the electrons as tightly bound to the atomic cores. (Coulomb interactions between electrons are still neglected.) The predictions of these two complementary models are reassuringly similar.
Ideas and assumptions
Predictions of the model This very simple model of metals more or less correctly predicts: Problems As not all the forces on the electrons are taken into account the electrons have an effective mass that is larger than the free electron model predicts. See also Free electron People Other | ||||||||||
|
| |||||||||||
![]() |
|
| |