<html xmlns="http://www.w3.org/1999/xhtml" xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office"><head><!--[if gte mso 9]><xml><o:OfficeDocumentSettings><o:AllowPNG/><o:PixelsPerInch>96</o:PixelsPerInch></o:OfficeDocumentSettings></xml><![endif]--></head><body><div class="ydp16730bb0yahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;"><div id="ydp16730bb0yiv0794508315"><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;" class="ydp16730bb0yiv0794508315ydpd3c4bb33yahoo-style-wrap"><div></div>
<div dir="ltr">Dear QE users,</div><div dir="ltr"><br clear="none"></div><div dir="ltr">Following is the input to the adsorption of Cl on Cr2O3, where a slab is created in the direction <001>:<br clear="none"></div><div dir="ltr"><br clear="none"></div><div dir="ltr">"</div><div dir="ltr"><div><div>&CONTROL</div><div> calculation = "relax"</div><div> forc_conv_thr = 1.00000e-03</div><div> max_seconds = 8.64000e+05</div><div> nstep = 501</div><div> pseudo_dir = "."</div><div>/</div><div><br clear="none"></div><div>&SYSTEM</div><div> constrained_magnetization = "none"</div><div> degauss = 2.00000e-02</div><div> ecutrho = 360</div><div> ecutwfc = 90</div><div> ibrav = 0</div><div> nat = 121</div><div> nosym = .TRUE.</div><div> nspin = 1</div><div> ntyp = 3</div><div> occupations = "smearing"</div><div> smearing = "gaussian"</div><div><br></div><div>/</div><div><br clear="none"></div><div>&ELECTRONS</div><div> conv_thr = 1.00000e-06</div><div> diago_david_ndim = 4</div><div> diagonalization = "david"</div><div> electron_maxstep = 501</div><div> mixing_beta = 1.00000e-01</div><div> mixing_mode = "plain"</div><div> mixing_ndim = 8</div><div> startingpot = "atomic"</div><div> startingwfc = "atomic+random"</div><div>/</div><div><br clear="none"></div><div>&IONS</div><div> ion_dynamics = "bfgs"</div><div>/</div><div><br clear="none"></div><div>&CELL</div><div> cell_dofree = "all"</div><div> cell_dynamics = "bfgs"</div><div> press = 0.00000e+00</div><div> press_conv_thr = 5.00000e-01</div><div>/</div><div><br clear="none"></div><div>K_POINTS {automatic}</div><div> 3 3 3 0 0 0</div><div><br clear="none"></div><div>CELL_PARAMETERS {angstrom}</div><div> 9.917520 0.000000 0.000000</div><div> -4.958760 8.588824 0.000000</div><div> 0.000000 0.000000 32.654000</div><div><br clear="none"></div><div>ATOMIC_SPECIES</div><div>Cr 51.99610 Cr.pbe-spn-kjpaw_psl.1.0.0.UPF</div><div>O 15.99940 O.pbe-n-kjpaw_psl.1.0.0.UPF</div><div>Cl 35.45270 Cl.pbe-n-kjpaw_psl.1.0.0.UPF</div><div><br clear="none"></div><div>ATOMIC_POSITIONS {crystal}</div><div>Cr 0.000000 0.000000 0.398385</div><div>Cr 0.500000 0.000000 0.398385</div><div>Cr 0.500000 0.500000 0.398385</div><div>Cr 0.000000 0.500000 0.398385</div><div>Cr 0.166667 0.333333 0.386590</div><div>Cr 0.666667 0.333333 0.386590</div><div>Cr 0.166667 0.833334 0.386590</div><div>Cr 0.666667 0.833334 0.386590</div><div>O 0.345700 0.000000 0.357795</div><div>O 0.845700 0.000000 0.357795</div><div>O 0.154300 0.154300 0.357795</div><div>O 0.654300 0.154300 0.357795</div><div>O 0.500000 0.345700 0.357795</div><div>O 0.000000 0.345700 0.357795</div><div>O 0.345700 0.500000 0.357795</div><div>O 0.845700 0.500000 0.357795</div><div>O 0.154300 0.654300 0.357795</div><div>O 0.654300 0.654300 0.357795</div><div>O 0.500000 0.845700 0.357795</div><div>O 1.000000 0.845700 0.357795</div><div>Cr 0.333333 0.166667 0.329000</div><div>Cr 0.833334 0.166667 0.329000</div><div>Cr 0.333333 0.666667 0.329000</div><div>Cr 0.833334 0.666667 0.329000</div><div>Cr 0.000000 0.000000 0.317204</div><div>Cr 0.500000 0.000000 0.317204</div><div>Cr 0.500000 0.500000 0.317204</div><div>Cr 0.000000 0.500000 0.317204</div><div>O 0.179033 0.012367 0.288409</div><div>O 0.679034 0.012367 0.288409</div><div>O 0.487633 0.166667 0.288409</div><div>O 0.987634 0.166667 0.288409</div><div>O 0.333333 0.320967 0.288409</div><div>O 0.833334 0.320967 0.288409</div><div>O 0.179033 0.512367 0.288409</div><div>O 0.679034 0.512367 0.288409</div><div>O 0.487633 0.666667 0.288409</div><div>O 0.987634 0.666667 0.288409</div><div>O 0.333333 0.820967 0.288409</div><div>O 0.833334 0.820967 0.288409</div><div>Cr 0.166667 0.333333 0.259614</div><div>Cr 0.666667 0.333333 0.259614</div><div>Cr 0.166667 0.833334 0.259614</div><div>Cr 0.666667 0.833334 0.259614</div><div>Cr 0.333333 0.166667 0.247819</div><div>Cr 0.833334 0.166667 0.247819</div><div>Cr 0.333333 0.666667 0.247819</div><div>Cr 0.833334 0.666667 0.247819</div><div>O 0.166667 0.179033 0.219024</div><div>O 0.666667 0.179033 0.219024</div><div>O 0.012367 0.333333 0.219024</div><div>O 0.512367 0.333333 0.219024</div><div>O 0.320967 0.487633 0.219024</div><div>O 0.820967 0.487633 0.219024</div><div>O 0.166667 0.679034 0.219024</div><div>O 0.666667 0.679034 0.219024</div><div>O 0.012367 0.833334 0.219024</div><div>O 0.512367 0.833334 0.219024</div><div>O 0.320967 0.987634 0.219024</div><div>O 0.820967 0.987634 0.219024</div><div>Cr 0.000000 0.000000 0.190229 0 0 0</div><div>Cr 0.500000 0.000000 0.190229 0 0 0</div><div>Cr 0.500000 0.500000 0.190229 0 0 0</div><div>Cr 0.000000 0.500000 0.190229 0 0 0</div><div>Cr 0.166667 0.333333 0.178433 0 0 0</div><div>Cr 0.666667 0.333333 0.178433 0 0 0</div><div>Cr 0.166667 0.833334 0.178433 0 0 0</div><div>Cr 0.666667 0.833334 0.178433 0 0 0</div><div>O 0.154300 0.000000 0.149638 0 0 0</div><div>O 0.654300 0.000000 0.149638 0 0 0</div><div>O 0.000000 0.154300 0.149638 0 0 0</div><div>O 0.500000 0.154300 0.149638 0 0 0</div><div>O 0.345700 0.345700 0.149638 0 0 0</div><div>O 0.845700 0.345700 0.149638 0 0 0</div><div>O 0.154300 0.500000 0.149638 0 0 0</div><div>O 0.654300 0.500000 0.149638 0 0 0</div><div>O 0.000000 0.654300 0.149638 0 0 0</div><div>O 0.500000 0.654300 0.149638 0 0 0</div><div>O 0.345700 0.845700 0.149638 0 0 0</div><div>O 0.845700 0.845700 0.149638 0 0 0</div><div>Cr 0.333333 0.166667 0.120843 0 0 0</div><div>Cr 0.833334 0.166667 0.120843 0 0 0</div><div>Cr 0.333333 0.666667 0.120843 0 0 0</div><div>Cr 0.833334 0.666667 0.120843 0 0 0</div><div>Cr 0.000000 0.000000 0.109048 0 0 0</div><div>Cr 0.500000 0.000000 0.109048 0 0 0</div><div>Cr 0.500000 0.500000 0.109048 0 0 0</div><div>Cr 0.000000 0.500000 0.109048 0 0 0</div><div>O 0.333333 0.012367 0.080253 0 0 0</div><div>O 0.833334 0.012367 0.080253 0 0 0</div><div>O 0.179033 0.166667 0.080253 0 0 0</div><div>O 0.679034 0.166667 0.080253 0 0 0</div><div>O 0.487633 0.320967 0.080253 0 0 0</div><div>O 0.987634 0.320967 0.080253 0 0 0</div><div>O 0.333333 0.512367 0.080253 0 0 0</div><div>O 0.833334 0.512367 0.080253 0 0 0</div><div>O 0.179033 0.666667 0.080253 0 0 0</div><div>O 0.679034 0.666667 0.080253 0 0 0</div><div>O 0.487633 0.820967 0.080253 0 0 0</div><div>O 0.987634 0.820967 0.080253 0 0 0</div><div>Cr 0.166667 0.333333 0.051458 0 0 0</div><div>Cr 0.666667 0.333333 0.051458 0 0 0</div><div>Cr 0.166667 0.833334 0.051458 0 0 0</div><div>Cr 0.666667 0.833334 0.051458 0 0 0</div><div>Cr 0.333333 0.166667 0.039662 0 0 0</div><div>Cr 0.833334 0.166667 0.039662 0 0 0</div><div>Cr 0.333333 0.666667 0.039662 0 0 0</div><div>Cr 0.833334 0.666667 0.039662 0 0 0</div><div>O 0.012367 0.179033 0.010868 0 0 0</div><div>O 0.512367 0.179033 0.010868 0 0 0</div><div>O 0.320967 0.333333 0.010868 0 0 0</div><div>O 0.820967 0.333333 0.010868 0 0 0</div><div>O 0.166667 0.487633 0.010868 0 0 0</div><div>O 0.666667 0.487633 0.010868 0 0 0</div><div>O 0.012367 0.679034 0.010868 0 0 0</div><div>O 0.512367 0.679034 0.010868 0 0 0</div><div>O 0.320967 0.833334 0.010868 0 0 0</div><div>O 0.820967 0.833334 0.010868 0 0 0</div><div>O 0.166667 0.987634 0.010868 0 0 0</div><div>O 0.666667 0.987634 0.010868 0 0 0</div><div>Cl 0.481508 0.500000 0.453947</div></div><br clear="none"></div><div dir="ltr">"</div><div dir="ltr"><br clear="none"></div><div dir="ltr"><b>The last part of the output gives:</b><br clear="none"><br clear="none">"</div><div dir="ltr">.</div><div dir="ltr">.</div><div dir="ltr"><div><div> bfgs converged in 40 scf cycles and 39 bfgs steps</div><div> (criteria: energy < 1.0E-04 Ry, force < 1.0E-03 Ry/Bohr)</div><div><br clear="none"></div><div> End of BFGS Geometry Optimization</div><div><br clear="none"></div><div> Final energy = <b> -3808.8434290038</b> Ry</div><div><br clear="none"></div></div><div>"</div><br clear="none"></div><div dir="ltr">The same input after removing Cl, i.e., only Cr2O3, yields a final energy of <b>-3729.3140139559 Ry</b>.</div><div dir="ltr"><br clear="none"></div><div dir="ltr"><br clear="none"></div><div dir="ltr">The same input with only Cl yields a final energy<span><b> of -79.2218317877 Ry.</b></span></div><div dir="ltr"><span><b><br clear="none"></b></span></div><div dir="ltr"><br></div><div dir="ltr">For calculating the adsorption energy of Cl on Cr2O3, the following equation is used:<br clear="none"><br clear="none"></div><div dir="ltr"><span><b>E(ads) = E(cr2o3+cl) − E <span><span style="color:rgb(0, 0, 0);font-family:Helvetica Neue, Helvetica, Arial, sans-serif;">(cr2o3)</span></span> − E(cl)</b></span><br clear="none"></div><div dir="ltr"><span><b><br></b></span></div><div dir="ltr" data-setdir="false">This gives us the adsorption energy of Cl on Cr2O3 as <b>-0.31 Ry (i.e., -<span>4.22 eV)</span></b></div><div dir="ltr" data-setdir="false"><b><span><br></span></b></div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">However, if we look at the literature, this value normally lies in the <b>positive region</b>, which is why Cr2O3 helps steel resist corrosion due to chlorine attack.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">In my calculation, this value is coming negative. If anyone can guide me in this regard, I will be really grateful.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Regards</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Akhil Nair</div><div dir="ltr" data-setdir="false">Research scholar</div><div dir="ltr" data-setdir="false">HBNI, India.</div><div dir="ltr"><span><b><br clear="none"></b></span></div><div dir="ltr"><br clear="none"></div>
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On Friday 30 August, 2024 at 05:51:41 pm IST, Akhil g.nair <akhilg.nair@yahoo.in> wrote:
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<div><div id="yiv0794508315"><div><div style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;" class="yiv0794508315ydp39a6f88dyahoo-style-wrap"><div dir="ltr">Dear QE users,</div><div dir="ltr"><br clear="none"></div><div dir="ltr">I was trying to calculate the adsorption energy of Cl on Cr2O3 using the following methodology :<br clear="none">"<a shape="rect" href="https://mattermodeling.stackexchange.com/questions/9888/adsorption-calcs-using-quantum-espresso" class="yiv0794508315ydp39a6f88denhancr_card_5550258368" target="_blank" rel="noreferrer noopener">Adsorption calcs using Quantum ESPRESSO</a>"<br clear="none"></div><div><br clear="none"></div><div id="yiv0794508315ydp8bea45ddenhancr_card_5550258368" style="max-width:400px;font-family:YahooSans VF, YahooSans, OpenSans VF, OpenSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif;position:relative;" data-url="https://mattermodeling.stackexchange.com/questions/9888/adsorption-calcs-using-quantum-espresso" data-type="YENHANCER" data-size="MEDIUM" class="yiv0794508315ydp8bea45ddyahoo-link-enhancr-card yiv0794508315ydp8bea45ddymail-preserve-class yiv0794508315ydp8bea45ddymail-preserve-style"><a shape="rect" href="https://mattermodeling.stackexchange.com/questions/9888/adsorption-calcs-using-quantum-espresso" style="text-decoration:none !important;color:#000 !important;" class="yiv0794508315ydp8bea45ddyahoo-enhancr-cardlink" target="_blank" rel="noreferrer noopener"><table border="0" cellpadding="0" cellspacing="0" style="max-width:400px;" class="yiv0794508315ydp8bea45ddcard-wrapper yiv0794508315ydp8bea45ddyahoo-ignore-table"><tbody><tr><td colspan="1" rowspan="1" width="400"><table border="0" cellpadding="0" cellspacing="0" width="100%" style="max-width:400px;border-width:1px;border-style:solid;border-color:rgb(224, 228, 233);border-radius:2px;" class="yiv0794508315ydp8bea45ddcard yiv0794508315ydp8bea45ddyahoo-ignore-table"><tbody><tr><td colspan="1" rowspan="1" valign="top" background="https://s.yimg.com/lo/api/res/1.2/YE7iyIOZ..fthgwnALPJ1Q--~A/Zmk9ZmlsbDt3PTQwMDtoPTIwMDthcHBpZD1pZXh0cmFjdA--/https://cdn.sstatic.net/Sites/mattermodeling/Img/apple-touch-icon@2.png?v=cc143db8c8c1.cf.jpg" bgcolor="#000000" height="175" style="background-color:rgb(0, 0, 0);background-repeat:no-repeat;background-size:cover;position:relative;border-radius:2px 2px 0px 0px;min-height:175px;" class="yiv0794508315ydp8bea45ddcard-primary-image-cell"><table border="0" cellpadding="0" cellspacing="0" style="width:100%;" class="yiv0794508315ydp8bea45ddcard-overlay-container-table yiv0794508315ydp8bea45ddyahoo-ignore-table"><tbody><tr><td colspan="1" rowspan="1" valign="top" background="https://s.yimg.com/cv/ae/nq/storm/assets/enhancrV21/1/enhancr_gradient-400x175.png" bgcolor="transparent" style="background-color:transparent;border-radius:2px 2px 0px 0px;min-height:175px;" class="yiv0794508315ydp8bea45ddcard-overlay-cell"><table border="0" height="175" style="width:100%;min-height:175px;" class="yiv0794508315ydp8bea45ddyahoo-ignore-table"><tbody><tr><td colspan="1" rowspan="1" style="text-align:left;padding:15px 0 0 15px;vertical-align:top;" class="yiv0794508315ydp8bea45ddcard-richInfo2"></td><td colspan="1" rowspan="1" style="text-align:right;padding:15px 15px 0 0;vertical-align:top;" class="yiv0794508315ydp8bea45ddcard-actions"><div class="yiv0794508315ydp8bea45ddcard-share-container"></div></td></tr></tbody></table></td></tr></tbody></table></td></tr><tr><td colspan="1" rowspan="1"><table align="center" border="0" cellpadding="0" cellspacing="0" style="background:#fff;position:relative;z-index:2;width:100%;max-width:400px;border-radius:0 0 2px 2px;border-top:1px solid rgb(224, 228, 233);" class="yiv0794508315ydp8bea45ddcard-info yiv0794508315ydp8bea45ddyahoo-ignore-table"><tbody><tr><td colspan="1" rowspan="1" style="background-color:#ffffff;padding:16px 0 16px 12px;vertical-align:top;border-radius:0 0 0 2px;"></td><td colspan="1" rowspan="1" style="vertical-align:middle;padding:12px 24px 16px 12px;width:99%;font-family:YahooSans VF, YahooSans, OpenSans VF, OpenSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif;border-radius:0 0 2px 0;"><h2 style="font-size:14px;line-height:19px;margin:0px 0px 6px;font-family:YahooSans VF, YahooSans, OpenSans VF, OpenSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif;color:rgb(29, 34, 40);max-width:314px;" class="yiv0794508315ydp8bea45ddcard-title">Adsorption calcs using Quantum ESPRESSO</h2><p style="font-size:12px;line-height:16px;margin:0px;color:rgb(151, 158, 168);" class="yiv0794508315ydp8bea45ddcard-description">I already built a copper surface using BURAI and I used an SCF calculation to find the total energy of this surf...</p></td></tr></tbody></table></td></tr></tbody></table></td></tr></tbody></table></a><div style="width:100%;min-height:100%;" class="yiv0794508315ydp39a6f88dloadingSpinnerContainer"><div class="yiv0794508315ydp39a6f88dD_F yiv0794508315ydp39a6f88dF_n yiv0794508315ydp39a6f88dgl_C yiv0794508315ydp39a6f88dab_C yiv0794508315ydp39a6f88dH_6MGW yiv0794508315ydp39a6f88do_h"><div class="yiv0794508315ydp39a6f88dW_6MGW yiv0794508315ydp39a6f88dH_6MGW yiv0794508315ydp39a6f88dD_X yiv0794508315ydp39a6f88dah_1PEzoz"></div></div></div></div><div><br clear="none"></div><div><br clear="none"></div><div dir="ltr">However, the values always come out to be negative. As per the literature [<a shape="rect" href="https://doi.org/10.1016/j.actamat.2023.119477" class="yiv0794508315ydp39a6f88denhancr_card_5807485004" target="_blank" rel="noreferrer noopener">Redirecting</a>], Cl adsorption on Cr2O3 should have positive energy.</div><div><br clear="none"></div><div id="yiv0794508315ydp888358b2enhancr_card_5807485004" style="max-width:400px;font-family:YahooSans VF, YahooSans, OpenSans VF, OpenSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif;" data-url="https://doi.org/10.1016/j.actamat.2023.119477" data-type="YENHANCER" data-size="MEDIUM" class="yiv0794508315ydp888358b2yahoo-link-enhancr-card yiv0794508315ydp888358b2yahoo-link-enhancr-not-allow-cover yiv0794508315ydp888358b2ymail-preserve-class yiv0794508315ydp888358b2ymail-preserve-style"><a shape="rect" href="https://doi.org/10.1016/j.actamat.2023.119477" style="text-decoration:none !important;color:#000 !important;" class="yiv0794508315ydp888358b2yahoo-enhancr-cardlink" target="_blank" rel="noreferrer noopener"><table border="0" cellpadding="0" cellspacing="0" style="max-width:400px;" class="yiv0794508315ydp888358b2card-wrapper yiv0794508315ydp888358b2yahoo-ignore-table"><tbody><tr><td colspan="1" rowspan="1" width="400"><table border="0" cellpadding="0" cellspacing="0" width="100%" style="max-width:400px;border-width:1px;border-style:solid;border-color:rgb(224, 228, 233);border-radius:2px;" class="yiv0794508315ydp888358b2card yiv0794508315ydp888358b2yahoo-ignore-table"><tbody><tr><td colspan="1" rowspan="1"><table border="0" cellpadding="0" cellspacing="0" style="background:#fff;position:relative;z-index:2;width:100%;max-width:400px;border-radius:0 0 2px 2px;border-top:1px solid rgb(224, 228, 233);" class="yiv0794508315ydp888358b2card-info yiv0794508315ydp888358b2yahoo-ignore-table"><tbody><tr><td colspan="1" rowspan="1" style="background-color:#ffffff;padding:16px 0 16px 12px;vertical-align:top;border-radius:0 0 0 2px;"></td><td colspan="1" rowspan="1" style="vertical-align:middle;padding:12px 24px 16px 12px;width:99%;font-family:YahooSans VF, YahooSans, OpenSans VF, OpenSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif;border-radius:0 0 2px 0;"><h2 style="font-size:14px;line-height:19px;margin:0px 0px 6px;font-family:YahooSans VF, YahooSans, OpenSans VF, OpenSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif;color:rgb(29, 34, 40);max-width:314px;" class="yiv0794508315ydp888358b2card-title">Redirecting</h2><p style="font-size:12px;line-height:16px;margin:0px;color:rgb(151, 158, 168);" class="yiv0794508315ydp888358b2card-description"></p></td></tr></tbody></table></td></tr></tbody></table></td></tr></tbody></table></a></div><div><br clear="none"></div><div><br clear="none"></div><div dir="ltr">Currently, I am taking the 'Final Energy' at the end of the output file from the QE calculation after the 'relax' calculation.</div><div dir="ltr"><br clear="none"></div><div dir="ltr">Please let me know if I should consider any other values or if the calculation methodology needs to be changed.</div><div dir="ltr"><br clear="none"></div><div dir="ltr"><br clear="none"></div><div dir="ltr">Regards</div><div dir="ltr"><br clear="none"></div><div dir="ltr">Akhil Nair</div><div dir="ltr">Research scholar</div><div dir="ltr">HBNI, India</div></div></div></div></div>
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