<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"></head><body><div>I guess you are dealing with a rare earth or lanthanoid element. I would play with gga+u at the very least.</div><div><br></div><div>This c/should fix the nonlinearity in the charge transfer to/from the adatom.</div><div><br></div><div>No guarantee that you get what you want but more imlortantly what the system really wants.</div><div><br></div><div>It depends on the surface workfunction in comparison to the element electron affinity.</div><div><br></div><div>Good luck,</div><div><br></div><div>Stefano</div><div id="composer_signature"><div style="font-size:85%;color:#575757" dir="auto">Sent from my Samsung Galaxy smartphone.</div></div><div><br></div><div style="font-size:100%;color:#000000"><!-- originalMessage --><div>-------- Original message --------</div><div>From: Christoph Wolf <wolf.christoph@qns.science> </div><div>Date: 08/12/2017 05:39 (GMT+01:00) </div><div>To: pw_forum@pwscf.org </div><div>Subject: [Pw_forum] charging a metal ion in front of insulating plane </div><div><br></div></div><div dir="ltr">Dear all,<div><br></div><div><br></div><div>I am struggling to charge a metal ion in front of an insulating MgO plane; I build an inversion symmetric 5-layer MgO plane and place an ion 2 A away from it. The relaxation of the system gives ~1.7 A for the neutral and 2.1 A for the (tot_charge=-1) charged ion. When looking at the projwfc.x output the "charge state" of the ion, despite being far away from the surface, is only marginally charged:</div><div><br></div><div>1) neutral case</div><div> pw.x: number of electrons = 1456.00</div><div>pw.x: total magnetization = 4.00 Bohr mag/cell</div><div>pw.x: atom: 181 charge: 13.7470 magn: 3.2676</div><div><div>projwfc.x: Atom # 181: total charge = 15.4842, s = 3.0695, p = 5.9947, d = 6.4201, </div><div><br></div><div><br></div><div>2) negatively charged</div><div>number of electrons = 1457.00<br></div><div>pw.x: total magnetization = 1.02 Bohr mag/cell</div><div>pw.x: atom: 181 charge: 13.8845 magn: 0.9465</div><div>total charge = 15.6842, s = 2.9801, p = 5.9931, d = 6.7109, <br></div><div><br></div>-- <br><div class="gmail_signature"><div dir="ltr">Postdoctoral Researcher<br>Center for Quantum Nanoscience, Institute for Basic Science<br>Ewha Womans University, Seoul, South Korea<blockquote type="cite" style="font-size:12.8px"><div dir="ltr"><div><div dir="ltr"></div></div></div></blockquote></div></div>
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