No idea why it is being truncated, so this time I'll start the email after the error message<div>---------------</div><div><div>From the forums:</div><div><br></div><div><a href="http://www.democritos.it/pipermail/pw_forum/2008-September/010123.html">http://www.democritos.it/pipermail/pw_forum/2008-September/010123.html</a></div>
<div><a href="http://www.democritos.it/pipermail/pw_forum/2010-February.txt">http://www.democritos.it/pipermail/pw_forum/2010-February.txt</a></div><div><br></div><div>I understand that the third derivatives were never implemented and</div>
<div>that only the LDA part was calculated, for the Perdew Zunger</div><div>parameterization. Is this third derivative the third derivative that</div><div>is mentioned in the routine PH/raman_mat.f90 (i.e, the third</div>
<div>derivative of the energy with respect to the atomic displacements and</div><div>with respect to two electric fields, as described in Lazzeri and</div><div>Mauri, PRL 90,036401)?</div><div><br></div><div>I am interested in getting a feel for what would be needed to</div>
<div>implement the third derivatives with GGA into the code, as well as</div><div>what sort of errors one might expect when using the third-order term</div><div>as currently coded with LDA pseudopotentials (comments in the forums</div>
<div>have hinted that the errors are likely small). The shift in the Raman</div><div>spectra for cd-Si is pretty minor when using a GGA pseudo compared to</div><div>that of an LDA calculation, but I wanted to be able to quantify the</div>
<div>error better for other systems where comparing the GGA raman spectra</div><div>to one calculated within LDA was not possible (e.g., when the system</div><div>doesn't exhibit a gap in LDA).</div><div><br></div><div>
Thanks for the help!</div><div><br></div><div>Best,</div><div>Brad</div><div>UC Berkeley</div></div><div><div><br></div><br><div class="gmail_quote">On Tue, Nov 9, 2010 at 5:59 PM, Brad Malone <span dir="ltr"><<a href="mailto:brad.malone@gmail.com">brad.malone@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">It appears that my last email was severely truncated on the mailing list (even though it looks fine in my outbox). Below is what is should have been:<div>
-----------------------</div><div><div><div></div><div class="h5"><span style="font-family:arial, sans-serif;font-size:13px;border-collapse:collapse;color:rgb(51, 51, 51)">Hi, I am seeking more information on the error<br>
<br>> from phq_setup : error # 1<br>> third order derivatives not implemented with GGA<br><br>From the forums:<br><br><a href="http://www.democritos.it/pipermail/pw_forum/2008-September/010123.html" style="color:rgb(61, 84, 89)" target="_blank">http://www.democritos.it/pipermail/pw_forum/2008-September/010123.html</a><br>
<a href="http://www.democritos.it/pipermail/pw_forum/2010-February.txt" style="color:rgb(61, 84, 89)" target="_blank">http://www.democritos.it/pipermail/pw_forum/2010-February.txt</a><br><br>I understand that the third derivatives were never implemented and<br>
that only the LDA part was calculated, for the Perdew Zunger<br>parameterization. Is this third derivative the third derivative that<br>is mentioned in the routine PH/raman_mat.f90 (i.e, the third<br>derivative of the energy with respect to the atomic displacements and<br>
with respect to two electric fields, as described in Lazzeri and<br>Mauri, PRL 90,036401)?<br><br>I am interested in getting a feel for what would be needed to<br>implement the third derivatives with GGA into the code, as well as<br>
what sort of errors one might expect when using the third-order term<br>as currently coded with LDA pseudopotentials (comments in the forums<br>have hinted that the errors are likely small). The shift in the Raman<br>spectra for cd-Si is pretty minor when using a GGA pseudo compared to<br>
that of an LDA calculation, but I wanted to be able to quantify the<br>error better for other systems where comparing the GGA raman spectra<br>to one calculated within LDA was not possible (e.g., when the system<br>doesn't exhibit a gap in LDA).<br>
<br>Thanks for the help!<br><br>Best,<br>Brad<br>UC Berkeley</span><br><br></div></div><div><div></div><div class="h5"><div class="gmail_quote">On Tue, Nov 9, 2010 at 5:00 PM, Brad Malone <span dir="ltr"><<a href="mailto:brad.malone@gmail.com" target="_blank">brad.malone@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi, I am seeking more information on the error<br>
<br>
> from phq_setup : error # 1<br>
> third order derivatives not implemented with GGA<br>
<br>
>From the forums:<br>
<br>
<a href="http://www.democritos.it/pipermail/pw_forum/2008-September/010123.html" target="_blank">http://www.democritos.it/pipermail/pw_forum/2008-September/010123.html</a><br>
<a href="http://www.democritos.it/pipermail/pw_forum/2010-February.txt" target="_blank">http://www.democritos.it/pipermail/pw_forum/2010-February.txt</a><br>
<br>
I understand that the third derivatives were never implemented and<br>
that only the LDA part was calculated, for the Perdew Zunger<br>
parameterization. Is this third derivative the third derivative that<br>
is mentioned in the routine PH/raman_mat.f90 (i.e, the third<br>
derivative of the energy with respect to the atomic displacements and<br>
with respect to two electric fields, as described in Lazzeri and<br>
Mauri, PRL 90,036401)?<br>
<br>
I am interested in getting a feel for what would be needed to<br>
implement the third derivatives with GGA into the code, as well as<br>
what sort of errors one might expect when using the third-order term<br>
as currently coded with LDA pseudopotentials (comments in the forums<br>
have hinted that the errors are likely small). The shift in the Raman<br>
spectra for cd-Si is pretty minor when using a GGA pseudo compared to<br>
that of an LDA calculation, but I wanted to be able to quantify the<br>
error better for other systems where comparing the GGA raman spectra<br>
to one calculated within LDA was not possible (e.g., when the system<br>
doesn't exhibit a gap in LDA).<br>
<br>
Thanks for the help!<br>
<br>
Best,<br>
Brad<br>
UC Berkeley<br>
</blockquote></div><br></div></div></div>
</blockquote></div><br></div>