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<div class="moz-cite-prefix">On 07/30/2014 04:43 PM, Kondaiah
Samudrala wrote:<br>
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cite="mid:CAKjMXpYYog1bN6tgEtbaKxd0LeFsFaUxvSZeuq6AFAfy95sizQ@mail.gmail.com"
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<pre style="color:rgb(0,0,0)">Respected Dr. Lorenzo Paulatto,</pre>
<pre style="color:rgb(0,0,0)">Thank you for Quick reply..May be it is basic and crude to ask like this.can you please explain me the <b>"</b><span style="font-family:arial"><b>displacement pattern of the atoms"</b> in pwscf output.. I am not clear..Otherwise please give me some path for understand the output.. </span></pre>
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They are not written on output, but they are at the end of the
dynamical matrix file. I<br>
<br>
For every phonon band at this q point you have the energy
(frequency) of the mode than the displacement. The displacement is a
3-component (x,y,z) complex vector for each atom., i.e. three
complex numbers that describe the displacement of each atom along x,
y and z.<br>
<br>
<br>
Here is an example from some random file I had on my PC, this system
includes 2 atoms:<br>
<br>
[...]<br>
Diagonalizing the dynamical matrix<br>
<br>
q = ( 0.000000000 0.500000000 0.000000000 )<br>
<br>
**************************************************************************<br>
freq ( 1) = -13.073222 [THz] = -436.075739 [cm-1]<br>
( -0.000000 0.000149 -0.000000 0.000000 -0.000000 0.000000 )<br>
( -1.000000 -0.000000 -0.000000 -0.000000 -0.000441 0.000000 )<br>
freq ( 2) = -13.073222 [THz] = -436.075739 [cm-1]<br>
( -0.000000 0.000000 -0.000000 0.000000 0.000000 -0.000149 )<br>
( -0.000441 -0.000000 -0.000000 -0.000000 1.000000 0.000000 )<br>
freq ( 3) = 25.614758 [THz] = 854.416345 [cm-1]<br>
( -0.000000 0.996054 -0.000000 -0.000000 -0.000000 0.087343 )<br>
( 0.015692 -0.000000 -0.000000 0.000000 0.001376 0.000000 )<br>
freq ( 4) = 25.614758 [THz] = 854.416345 [cm-1]<br>
( -0.000000 0.087343 -0.000000 0.000000 0.000000 -0.996054 )<br>
( 0.001376 -0.000000 -0.000000 0.000000 -0.015692 0.000000 )<br>
freq ( 5) = 30.812798 [THz] = 1027.804323 [cm-1]<br>
( -0.000000 0.000000 0.000001 0.437588 0.000000 0.000000 )<br>
( 0.000000 -0.000000 0.899176 -0.000002 0.000000 -0.000000 )<br>
freq ( 6) = 37.682257 [THz] = 1256.944790 [cm-1]<br>
( 0.000000 -0.000000 0.000000 0.019458 0.000000 0.000000 )<br>
( -0.000000 0.000000 -0.999811 0.000000 0.000000 0.000000 )<br>
**************************************************************************<br>
<br>
You can see that bands 1, 2, 3 and 4 are transverse, band 5 and 6
are longitudinal.<br>
<br>
HTH<br>
<br>
<br>
<pre class="moz-signature" cols="72">--
Dr. Lorenzo Paulatto
IdR @ IMPMC -- CNRS & Université Paris 6
+33 (0)1 44 275 084 / skype: paulatz
<a class="moz-txt-link-freetext" href="http://www.impmc.upmc.fr/~paulatto/">http://www.impmc.upmc.fr/~paulatto/</a>
23-24/4é16 Boîte courrier 115, 4 place Jussieu 75252 Paris Cédex 05</pre>
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