The first chapter of Ashcroft and Mermin's Solid State Physics discusses electromagnetic waves in metals. One of the exercises requires calculation of the plasma frequency. For iron, I got 11.5 for the angular frequency (radians per second). This seems to low. Is it?

$\omega_p^2=\frac{4\pi n e^2}{m}$ where n is the density of charge carriers, e is the electron charge and m is the electron mass. The authors seem to be using gaussian units although this is not entirely clear. For n I used $1.7*10^{23}\:cm^{-3}$

My cyclotron frequency for a magnetic field of 10 kilogauss, $1.76*10^{11}$, seems to be right.

The first chapter of Ashcroft and Mermin's Solid State Physics discusses electromagnetic waves in metals. One of the exercises requires calculation of the plasma and helicon frequenies using the Drude model. For iron, I got $2.3*10^{16}$ for the plasma frequency and 11.5 for helicon wave frequency (radians per second). The first seems too high and the second seems too low. Are they reasonable?

The given formula for the plasma frequency is $\omega_p^2=\frac{4\pi n e^2}{m}$ where n is the density of charge carriers, e is the electron charge and m is the electron mass. The authors seem to be using gaussian units although this is not entirely clear. For n I used $1.7*10^{23}\:cm^{-3}$

My cyclotron frequency for a magnetic field of 10 kilogauss, $1.76*10^{11}$, seems to be right.

For the helicon wave frequency the given formula is $\omega=\omega_c(\frac{k^2c^2}{\omega_p^2})$ where $\omega_c$ is the cyclotron frequency and $\omega_p$ is the plasma frequency. The value of $k=2\pi/\lambda$ correesponds to wavelength of 1 cm.