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Dear Wien2k users<br>
<br>
I am interested in calculating the ELNES spectrum for a crystal and I
am faced with the following problems :<br>
<br>
Problem-1<br>
For an "Orientation Sensitive" calculation the Euler angles (alpha,
beta, gamma) are required. <br>
The crystal structure is described with respect to an Oxyz system. <br>
What should be the input for (alpha, beta, gamma) in order to have the
e-beam along the x-axis or y-axis or along <br>
an arbitrary direction (theta,phi) ? I understand that the question is
related to the definition of Euler angles adopted<br>
in the code. <br>
In the UG (pg.129) it is said that "This key ...to use the particular
sample-to-beam orientation defined by the 3 Euler angles."<br>
However it is not clear to me what this relative orientation
corresponds to when for example the input (alpha, beta, gamma)=(0,0,0)<br>
is used.<br>
<br>
Problem-2 <br>
I followed the steps :<br>
- recompiled lapw2 setting LXDOS=3 in modules.F (as suggested)<br>
- Initialization (using ISPLIT=4 in the case.struct file).<br>
- ran SCF<br>
- changed to ISPLIT=99 in case.struct. <br>
- edited case.innes (using w2web)<br>
- x lapw2 -qtl -c (using w2web) => got the following error message<br>
<h2>----------------------- error message --------------------<br>
</h2>
<h2><font color="#ff0000">Modified lapw2 -qtl for TELNES.2</font></h2>
<p><font color="#ff0000">calculation is orientation sensitive -> we
need ISPLIT=99</font></p>
<ul>
<li><font color="#ff0000">backing up AB.struct</font></li>
<li><font color="#ff0000">set ISPLIT=99 for atom 2</font></li>
<font color="#ff0000"><b>Error</b> - incorrect space group symbol<br>
<b>Error</b> - incorrect space group symbol<br>
</font>
<li><font color="#ff0000">write modified AB.struct</font></li>
<li><font color="#ff0000"><b>command:</b> x lapw2 -qtl -c </font>
<p><font color="#ff0000"><b>output</b>:<br>
</font></p>
<pre><font color="#ff0000">x lapw2 -qtl -c
Abort
7.768u 0.556s 0:02.35 353.6% 0+0k 0+0io 0pf+0w
error: command /home/dimitris/Programs/wien2k/8.2/lapw2c lapw2.def failed
</font></pre>
</li>
<li><font color="#ff0000">restore AB.struct</font></li>
</ul>
<h2>-----------------end of error message --------------------</h2>
Then turned to the console and gave exactly the same command (x lapw2
-qtl -c)<br>
and everything proceeded fine (empty lapw2.error file).<br>
Continued with w2web and got the spectrum eventually.<br>
Is it clear to anyone why this is happening ?<br>
<br>
DK<br>
<br>
<br>
<br>
-- <br>
----------------------------------------------------------<br>
<br>
Dr Dimitris Kechrakos<br>
Institute of Materials Science <br>
National Center of Scientific Research "Demokritos"<br>
153 10 - Agia Paraskevi<br>
Athens, GR<br>
tel: +30-210-650 3335 <br>
fax: +30-210-653 3872<br>
email: <a class="moz-txt-link-abbreviated" href="mailto:dkehrakos@ims.demokritos.gr">dkehrakos@ims.demokritos.gr</a>, <a class="moz-txt-link-abbreviated" href="mailto:physengin@gmail.com">physengin@gmail.com</a><br>
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