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<p style="MARGIN: 0in 0in 0pt" class="MsoNormal"><font size="3"><font face="Calibri">Hello!
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<p style="MARGIN: 0in 0in 0pt" class="MsoNormal"><font size="3"><font face="Calibri">When I do a volume optimization of keeping the a:b:c ratio fixed (option 1), I get a discontinuity in the E vs. V curve.
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<p style="MARGIN: 0in 0in 0pt" class="MsoNormal"><font size="3"><font face="Calibri">I am using a 32 atom supercell with an impurity. My parameters where initially at first RMT(1) = 2.5 and RMT(2) = 2.3 and RKmax = 8.0. I get the discontinuity at approximately
volume contraction of 6%. To fix the problem I have tried three separate calculations: <o:p></o:p></font></font></p>
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<span style="mso-fareast-font-family: Calibri"><span style="mso-list: Ignore"><font size="3" face="Calibri">1)</font><span style="FONT: 7pt 'Times New Roman'">
</span></span></span><font size="3"><font face="Calibri">Increasing the emax value in the *.in1 file from the default value of 2.5 to 3.
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<span style="mso-fareast-font-family: Calibri"><span style="mso-list: Ignore"><font size="3" face="Calibri">2)</font><span style="FONT: 7pt 'Times New Roman'">
</span></span></span><font size="3"><font face="Calibri">Increasing the RKmax to 9.<o:p></o:p></font></font></p>
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<span style="mso-fareast-font-family: Calibri"><span style="mso-list: Ignore"><font size="3" face="Calibri">3)</font><span style="FONT: 7pt 'Times New Roman'">
</span></span></span><font size="3"><font face="Calibri">Keeping RKmax at 9 and changing the RMT(2) to 2.13.
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<p style="MARGIN: 0in 0in 0pt" class="MsoNormal"><font size="3"><font face="Calibri">All four separate calculations gave me the same discontinuity. Note atom 2 radius is about 15% smaller than atom 1 radius and atom 2 is the impurity. Any guidance or suggestions
will be greatly appreciated.<o:p></o:p></font></font></p>
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<p style="MARGIN: 0in 0in 0pt" class="MsoNormal"><font size="3"><font face="Calibri">Thank you,<o:p></o:p></font></font></p>
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<p style="MARGIN: 0in 0in 0pt" class="MsoNormal"><font size="3"><font face="Calibri">Sarah Hernandez<o:p></o:p></font></font></p>
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