# I Density of States Derivation

#### iampaul

Summary
I tried to follow the derivation, but I got a different result
I was looking for a derivation for the density of states and I came across this page: https://ecee.colorado.edu/~bart/book/book/chapter2/ch2_4.htm

I followed the derivation and came up with:
g(E) = (1/L3)dN/dE
= (1/L3)L3/2*k2 * dk/dE
=K2/2 * dk/dE
=K2/2 *
g(E) = (∏√2/h3)*m3/2*√2

but the book gives:
g(E) = (8∏√2/h3)*m3/2*√2

where did the extra 8 come from?

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#### BvU

Homework Helper
Check your math. You miss some factors $\pi$.
The 8 comes from the $\ \hbar^3\$ and $\ \hbar = {h\over2\pi}$

#### iampaul

Check your math. You miss some factors $\pi$.
The 8 comes from the $\ \hbar^3\$ and $\ \hbar = {h\over2\pi}$
Thanks, i've been plugging in $\ \hbar = {h\over\pi}$.

"Density of States Derivation"

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