# Radius of the fermi sphere

1. ### ehrenfest

[SOLVED] radius of the fermi sphere

1. The problem statement, all variables and given/known data
On page 249 of ISSP, Kittel says that the radius of a free electron Fermi sphere is

$$k_F = \left(3 \pi^2 n \right)^{1/3}$$

where n is the concentration of electrons.

I don't know why that is true.

EDIT: never mind; they derive that on page 138

2. Relevant equations

3. The attempt at a solution

Last edited: Mar 30, 2008
2. ### MeChaState

17
Re: [SOLVED] radius of the fermi sphere

Are you still interested in an answer?