<html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"> <head> <meta http-equiv="Content-Type" content="text/html; charset=Windows-1252"> <meta name="Generator" content="Microsoft Word 15 (filtered medium)"> <style></style> </head> <body lang="en-CH" link="blue" vlink="purple" style="word-wrap:break-word"> <div class="WordSection1"> <p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-fareast-language:EN-US">Hi Michael<o:p></o:p></span></p> <p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p> <p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-fareast-language:EN-US">The error occurs, because MULTIPLICITY must be set to 3 in that case also for the calculation of a restricted open-shell singlet with OT. That defines the number of open shell orbitals involved in the calculation. OT includes only the occupied orbitals and the calculated “base” term is a triplet. Have a look at the CP2K test input tests/QS/regtest-lsroks/O2.inp. Note that the terms defined by SPIN_CONFIGURATION are additional terms which are added to the triplet (base) term which is calculated in any case.<o:p></o:p></span></p> <p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p> <p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-fareast-language:EN-US">HTH<o:p></o:p></span></p> <p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p> <p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-fareast-language:EN-US">Matthias<o:p></o:p></span></p> <p class="MsoNormal"><span lang="EN-US" style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p> <div id="mail-editor-reference-message-container"> <div> <div> <div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm"> <p class="MsoNormal" style="mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:12.0pt;margin-left:36.0pt"> <b><span style="color:black">From: </span></b><span style="color:black">cp2k@googlegroups.com <cp2k@googlegroups.com> on behalf of Michael LaCount <lacount.mi@gmail.com><br> <b>Date: </b>Monday, 25 August 2025 at 07:28<br> <b>To: </b>cp2k <cp2k@googlegroups.com><br> <b>Subject: </b>[CP2K:21773] restricted open-shell Kohn-Sham (ROKS) Setup<o:p></o:p></span></p> </div> <p class="MsoNormal" style="margin-left:36.0pt">Hello I am trying to set up a fairly simple test run for ROKS. The simplest test I could think of for what I want to try to do is to set up 2 jobs, both will have a Na and Cl atom placed 1nm apart and with periodic boundary conditions turned off (and 1nm from nearest box wall). The 2 jobs differ in that I want the first to converge to neutral atoms, and the second to converge to ions. My understanding with ROKS is that this should be doable and fairly easy.<o:p></o:p></p> <div> <p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt">My jobs are running into an error. CPASSERT failed qs_ks_utils.F:263, so there is something wrong with my setup. The CPASSERT in question is:<o:p></o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt"> CPASSERT(Nelectron == k_alpha - k_beta)<o:p></o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt">The CP2K code block I am using is:<o:p></o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt"> &DFT<br> CHARGE 0<br> MULTIPLICITY 1<br> UKS<br> ROKS<br> &LOW_SPIN_ROKS<br> ENERGY_SCALING 1 -1 1 -1<br> SPIN_CONFIGURATION 1 1<br> SPIN_CONFIGURATION 1 2<br> SPIN_CONFIGURATION 2 2<br> SPIN_CONFIGURATION 2 1<br> &END LOW_SPIN_ROKS<o:p></o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt">...<o:p></o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt"> &END DFT<o:p></o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt">My interpretation of how this would work is that it would find 2 unpaired electron levels: an 's' for Na and a 'p' for Cl. This would then bias the two orbitals to a certain spin. I don't think I am understanding the syntax of these commands properly and would like some guidance on how to properly cover the 2 scenarios I mentioned (neutral Na/Cl and ionic Na/Cl in a non-periodic box).<o:p></o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt"><o:p> </o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt">Thanks<o:p></o:p></p> </div> <div> <p class="MsoNormal" style="margin-left:36.0pt">Michael<o:p></o:p></p> </div> <p class="MsoNormal" style="margin-left:36.0pt">-- <br> You received this message because you are subscribed to the Google Groups "cp2k" group.<br> To unsubscribe from this group and stop receiving emails from it, send an email to <a href="mailto:cp2k+unsubscribe@googlegroups.com">cp2k+unsubscribe@googlegroups.com</a>.<br> To view this discussion visit <a href="https://groups.google.com/d/msgid/cp2k/209eb892-0358-40ef-bf69-2e370dc8cba0n%40googlegroups.com?utm_medium=email&utm_source=footer"> https://groups.google.com/d/msgid/cp2k/209eb892-0358-40ef-bf69-2e370dc8cba0n%40googlegroups.com</a>.<o:p></o:p></p> </div> </div> </div> </div> </body> </html> <p></p> -- <br /> You received this message because you are subscribed to the Google Groups "cp2k" group.<br /> To unsubscribe from this group and stop receiving emails from it, send an email to <a href="mailto:cp2k+unsubscribe@googlegroups.com">cp2k+unsubscribe@googlegroups.com</a>.<br /> To view this discussion visit <a href="https://groups.google.com/d/msgid/cp2k/ZR2P278MB114678061AC9822F91883D7BF40FA%40ZR2P278MB1146.CHEP278.PROD.OUTLOOK.COM?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/ZR2P278MB114678061AC9822F91883D7BF40FA%40ZR2P278MB1146.CHEP278.PROD.OUTLOOK.COM</a>.<br />