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<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">I</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">’</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">ve been assuming the units of charge density as stored</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">in *.save and used in plotrho and accessed by xcrysden are scaled as (number of electrons</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">/angstroms^3), but just thought I</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">’</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">d better check. Looking at the codes, examples and t</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">utorials available for PWscf, I couldn</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">’</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">t find</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">any explicit confirmation (I</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">’</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">m sure there is somewhere)</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">that</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">this is indeed the case. I could try perf</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">orming a volumetric integration on some simple example</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">, but thought I</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">’</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">d ask the community first.</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> It seems this is the case just by looking at the contours and surfaces</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">produced by xcrysden, but I</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">’</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">m not too sure what the cryptic notation</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">“</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">delta n(r)</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">”</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> defines. I</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">take</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> it</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">’</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">s the differential between isolevels in</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">the</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">un</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">its I</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">’</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">ve</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">been using</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">.</FONT></SPAN><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Also, some time</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">ago</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> (about three months!), I switched from espresso-3.2.3 to o-sesa</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">me, and noticed that the charge density files in *.save are in a</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">*.dat binary format rather than *.xml. What</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">’</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">s going to be the future standard?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Finally, and I think I asked about this before,</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">is there a developers guide to the bowels of pw.x? The makefile links an enormous number of object</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">files and I suppose one could figure this all out. Surely, there have been courses given</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> at SISSA</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> on its</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> internal structure, if only in the shape of a flow chart. If these lectures</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">are</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> in Italian, no problem,</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">and I would make a translation available to all.</FONT></SPAN><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Ciao, -Paul</FONT></SPAN><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><B><I></I></B></SPAN><SPAN LANG="en-us"><B><I></I></B></SPAN><SPAN LANG="en-us"><B><I></I></B></SPAN><B><I><SPAN LANG="en-us"><FONT SIZE=4 FACE="Comic Sans MS">Paul M. Grant, PhD</FONT></SPAN></I></B><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><B></B></SPAN><SPAN LANG="en-us"><B></B></SPAN><SPAN LANG="en-us"><B></B></SPAN><B><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">Principal, W2AGZ Technologies</FONT></SPAN></B><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><B></B></SPAN><SPAN LANG="en-us"><B></B></SPAN><SPAN LANG="en-us"><B></B></SPAN><B><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">Visiting Scholar, Applied Physics, Stanford University</FONT></SPAN></B><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><B></B></SPAN><SPAN LANG="en-us"><B></B></SPAN><SPAN LANG="en-us"><B></B></SPAN><B><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">EPRI Science Fellow (Retired)</FONT></SPAN></B><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><B></B></SPAN><SPAN LANG="en-us"><B></B></SPAN><SPAN LANG="en-us"><B></B></SPAN><B><SPAN LANG="en-us"><FONT SIZE=2 FACE="Arial">IBM Research Staff Member Emeritus</FONT></SPAN></B><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN><SPAN LANG="en-us"></SPAN></P>
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