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<div class="moz-cite-prefix">I haven't calculated the effective mass
with WIEN2k, but my current understanding is as follows.<br>
<br>
One method used to calculate the effective mass is the parabolic
approximation method.<br>
<br>
You can probably find this method described in semiconductor
physics or solid state physics textbooks. I find the description
of the parabolic approximation method in section "3.2.3 Electron
Effective Mass" of the book titled "<span class="a-size-large"
id="productTitle">Semiconductor Physics and Devices, 3rd Edition</span>"
by Donald Neamen useful. Maybe others know of other good
references.<br>
<b><br>
</b><b>Summary of the parabolic approximation method</b><br>
<br>
1) Calculate the bandstructure (E-k: energy versus k) using
WIEN2k.<br>
<br>
2) Plot E-k<br>
<br>
3) Using the E and k values from WIEN2k, fit the desired data
points to the equation for a parabola [
<a class="moz-txt-link-freetext" href="http://www.mail-archive.com/wien%40zeus.theochem.tuwien.ac.at/msg04621.html">http://www.mail-archive.com/wien%40zeus.theochem.tuwien.ac.at/msg04621.html</a>
]. For example, if fitting to the conduction band, the equation E
= C1(k)^2 + Ec is used, which comes from equation 3.44 in the "<span
class="a-size-large" id="productTitle">Semiconductor Physics And
Devices</span>" book.<br>
<br>
To fit the parabolic equation to the band, you should be able to
use your favorite curve fit program like Matlab, Origin, or Octave
to obtain the curve fitting parameters C1 and Ec. The polyfit
function might useful, if you use Matlab [
<a class="moz-txt-link-freetext" href="http://www.mathworks.com/matlabcentral/newsreader/view_thread/23793">http://www.mathworks.com/matlabcentral/newsreader/view_thread/23793</a>
].<br>
<br>
4) Plot the E equation (equation of the parabola) on the same E-k
plot (of step 2) to visualize the wellness of the fit.<br>
<br>
5) Substitute the E equation into the effective mass equation
followed by taking the second derivative with respect to k to
calculate the effective mass. In other words, plug E (e.g., E =
C1(k)^2 + Ec) into the equation 1/m* = 1/hbar*d^2E/dk^2 and solve
for the effective mass m* (equation 3.47 in "<span
class="a-size-large" id="productTitle">Semiconductor Physics And
Devices</span>").<br>
<br>
Another approach is the finite difference method. Unfortunately,
I don't know of any tools for WIEN2k that can currently do this.
There is an Effective Mass Calculator (EMC) for VASP, but it does
not support WIEN2k [ <a class="moz-txt-link-freetext" href="http://afonari.com/emc/">http://afonari.com/emc/</a> ]. However, you
might trying contacting an author of the EMC to see if there are
any future plans to support WIEN2k, and let us know what you find
out. Though, it might be a good project for someone in the WIEN2k
community. If a conversion program was made to convert the WIEN2k
output to VASP format or reading of the needed WIEN2k output was
implemented in the EMC source code, I think the EMC could be made
to work.<br>
<br>
On 11/18/2014 4:20 AM, ben amara imen wrote:<br>
</div>
<blockquote
cite="mid:CACAZvnpa=a9+Oq4NJ1gzsTwVB37j7rOyVoDhb9U5RCU7y08dZw@mail.gmail.com"
type="cite">
<div dir="ltr">Dear all,
<div><br>
</div>
<div>Can some one help me how I can calculate the effective
masse of hole and electron , from the structure bands ??</div>
<div>Thanks in advance</div>
<div>Best Regards</div>
<div>Imen</div>
</div>
</blockquote>
<br>
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