<div dir="ltr"><div>Thanks Juerg. I will try as you suggest and update a few days later.</div><div> </div> On Monday, April 6, 2020 at 3:32:56 PM UTC+8, jgh wrote:<blockquote class="gmail_quote" style="margin: 0;margin-left: 0.8ex;border-left: 1px #ccc solid;padding-left: 1ex;">Hi I assume your system is weakly bound in z-direction. Small force changes in that direction can cause large changes. The only obvious problem I could spot is the definition of the reference cell. In order to minimize the effect of a change in volume, the reference cell should be larger than the initial and final cell. I would set c=10 or 12 and I would also increase the cutoff. You could test this by just scan the energy as function of c and correctly adapt the geometry of course. regards Juerg Hutter -------------------------------------------------------------- Juerg Hutter Phone : ++41 44 635 4491 Institut für Chemie C FAX : ++41 44 635 6838 Universität Zürich E-mail: <a href="javascript:" target="_blank" gdf-obfuscated-mailto="MLWfs5WrAwAJ" rel="nofollow" onmousedown="this.href='javascript:';return true;" onclick="this.href='javascript:';return true;">h...@chem.uzh.ch</a> Winterthurerstrasse 190 CH-8057 Zürich, Switzerland --------------------------------------------------------------- -----<a href="javascript:" target="_blank" gdf-obfuscated-mailto="MLWfs5WrAwAJ" rel="nofollow" onmousedown="this.href='javascript:';return true;" onclick="this.href='javascript:';return true;">c...@googlegroups.com</a> wrote: ----- To: "cp2k" <<a href="javascript:" target="_blank" gdf-obfuscated-mailto="MLWfs5WrAwAJ" rel="nofollow" onmousedown="this.href='javascript:';return true;" onclick="this.href='javascript:';return true;">c...@googlegroups.com</a>> From: "Linfeng Gan" Sent by: <a href="javascript:" target="_blank" gdf-obfuscated-mailto="MLWfs5WrAwAJ" rel="nofollow" onmousedown="this.href='javascript:';return true;" onclick="this.href='javascript:';return true;">c...@googlegroups.com</a> Date: 04/05/2020 04:27AM Subject: [CP2K:13056] COF cell optimize exploded Hello all, I need some help about the covalent-organic frameworks (COF) 2D sheet cell optimize. After I optimized the COF with a 2X2X2 supercell, the cell size was totally exploded. I had kept the cell vectors and symmetry constant, changed different basis sets and different XC functions but the cell exploded anyway. I had tried basis sets DZVP-MOLOPT-GTH and DZVP-MOLOPT-SR-GTH with PADE, PBE and BLYP. And the DFTD3 correction was also add to each calculation. The GAPW method I also had tried, but none of them worked. Any suggestion is welcome, thanks! Linfeng The COF-5-2X2X2 supercell vectors should be: CELL_TOP| Volume [angstrom^3]: 21253.270 CELL_TOP| Vector a [angstrom 60.040 0.000 0.000 |a| = 60.040 CELL_TOP| Vector b [angstrom -30.020 51.996 0.000 |b| = 60.040 CELL_TOP| Vector c [angstrom 0.000 0.000 6.808 |c| = 6.808 CELL_TOP| Angle (b,c), alpha [degree]: 90.000 CELL_TOP| Angle (a,c), beta [degree]: 90.000 CELL_TOP| Angle (a,b), gamma [degree]: 120.000 But after cell optimized calculation the output cell vectors are: ******************************************************************************* *** GEOMETRY OPTIMIZATION COMPLETED *** ******************************************************************************* Reevaluating energy at the minimum CELL| Volume [angstrom^3]: 25653.623 CELL| Vector a [angstrom]: 60.345 0.000 0.000 |a| = 60.345 CELL| Vector b [angstrom]: -30.173 52.260 0.000 |b| = 60.345 CELL| Vector c [angstrom]: 0.000 -0.000 8.135 |c| = 8.135 CELL| Angle (b,c), alpha [degree]: 90.000 CELL| Angle (a,c), beta [degree]: 90.000 CELL| Angle (a,b), gamma [degree]: 120.000 -- You received this message because you are subscribed to the Google Groups "cp2k" group. To unsubscribe from this group and stop receiving emails from it, send an email to <a href="javascript:" target="_blank" gdf-obfuscated-mailto="MLWfs5WrAwAJ" rel="nofollow" onmousedown="this.href='javascript:';return true;" onclick="this.href='javascript:';return true;">cp...@googlegroups.com</a>. To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/2da4af3b-2dcf-46c3-a49e-3dc62b170405%40googlegroups.com" target="_blank" rel="nofollow" onmousedown="this.href='https://groups.google.com/d/msgid/cp2k/2da4af3b-2dcf-46c3-a49e-3dc62b170405%40googlegroups.com';return true;" onclick="this.href='https://groups.google.com/d/msgid/cp2k/2da4af3b-2dcf-46c3-a49e-3dc62b170405%40googlegroups.com';return true;">https://groups.google.com/d/msgid/cp2k/2da4af3b-2dcf-46c3-a49e-3dc62b170405%40googlegroups.com</a>. [attachment "COF-5-2X2X2.xyz" removed by Jürg Hutter/at/UZH] [attachment "opt_cell.inp" removed by Jürg Hutter/at/UZH] </blockquote></div>