<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Dear sir/madam,<div class=""><br class=""></div><div class="">As I am using the ev.x to fitting EOS on Pd. I got the wrong bulk modulus. Here is my procedure. Please help me check what’s wrong with my fitting? </div><div class="">input data in Å and ev.</div><div class=""><br class=""></div><div class=""><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class="">3.7351 -1.455513098</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class="">3.8129 -1.5041846</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class="">3.8907 -1.527184909</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class="">3.9685 -1.530334715</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class="">4.0463 -1.51819883</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class="">4.1241 -1.4945274</div></div><div class=""><br class=""></div><div class=""><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class=""> Lattice parameter or Volume are in (au, Ang) > Ang</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class=""> Assuming Angstrom</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class=""> Enter type of bravais lattice (fcc, bcc, sc, noncubic) > fcc</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class=""> Enter type of equation of state :</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class=""> 1=birch1, 2=birch2, 3=keane, 4=murnaghan > 2</div></div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class="">then I get the output file like below:</div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class=""><br class=""></div><div style="margin: 0px; font-size: 11px; font-family: Menlo;" class=""><div style="margin: 0px; color: rgb(83, 48, 225);" class=""># equation of state: birch 3rd order. chisq = 0.3034D-10</div><div style="margin: 0px; color: rgb(83, 48, 225);" class=""># a0 = 7.4514 a.u., k0 = 6726 kbar, dk0 = 5.51 d2k0 = -0.001 emin = -1.53118</div><div style="margin: 0px;" class=""><span style="color: rgb(83, 48, 225);" class=""># a0 = 3.94309 Ang, </span><font color="#e32400" class="">k0 = 672.7 GPa</font><font color="#5330e1" class="">, V0 = 103.430 (a.u.)^3, V0 = 15.327 A^3 </font></div><div style="margin: 0px; min-height: 13px;" class=""><br class=""></div><div style="margin: 0px; color: rgb(83, 48, 225);" class="">#########################################################################</div><div style="margin: 0px; color: rgb(83, 48, 225);" class=""># Lat.Par E_calc E_fit E_diff Pressure Enthalpy</div><div style="margin: 0px; color: rgb(83, 48, 225);" class=""># Ang Ry Ry Ry GPa Ry</div><div style="margin: 0px; color: rgb(83, 48, 225);" class="">#########################################################################</div><div style="margin: 0px;" class=""> 3.73510 -1.45551 -1.45551 0.00000 170.75 -0.43510</div><div style="margin: 0px;" class=""> 3.81290 -1.50418 -1.50418 -0.00000 89.34 -0.93621</div><div style="margin: 0px;" class=""> 3.89070 -1.52718 -1.52719 0.00001 30.14 -1.32358</div><div style="margin: 0px;" class=""> 3.96850 -1.53033 -1.53033 -0.00001 -12.29 -1.61843</div><div style="margin: 0px;" class=""> 4.04630 -1.51820 -1.51820 0.00001 -42.10 -1.83804</div><div style="margin: 0px;" class=""> 4.12410 -1.49453 -1.49453 -0.00000 -62.42 -1.99662</div><div style="margin: 0px; color: rgb(94, 52, 255);" class="">~ </div><div style="margin: 0px;" class="">The k0 here is 672.7GPa, it should be 180GPa more or less. And I fitted same data with another software, it gives me 167GPa.</div><div style="margin: 0px;" class=""><br class=""></div><div style="margin: 0px;" class="">So Please Help Me What’s Wrong With My Fitting?</div><div style="margin: 0px;" class=""><br class=""></div><div style="margin: 0px;" class="">Thank you!!!</div><div style="margin: 0px;" class=""><br class=""></div><div style="margin: 0px;" class="">best</div><div style="margin: 0px;" class="">xiao</div><div style="margin: 0px;" class=""> </div></div></body></html>