free electron model

[omri3012]

Hallo,

i would like to know why do we use the term free electron gas instead of Plasma?
aren't both the same?

thanks,
Omri

[ppdbacke]

While free electron model specifically deals with electrons, a plasma generally consists of both electrons and positively ionized atoms.

[Mute]

They are not the same. The free electron model assumes that interactions between the electrons are negligible and hence completely neglected. In a plasma the interactions between the electrically charged elements are very strong. Perhaps some models of plasmas may be equivalent to the free electron model, in a mean-field kind of approximation, but more sophisticated models will be very different from the free electron model.