<div dir="ltr"><div style="background-color: rgb(250, 250, 250); border-color: rgb(187, 187, 187); border-style: solid; border-width: 1px; overflow-wrap: break-word;" class="prettyprint"><code class="prettyprint"><div class="subprettyprint">4 Lattice="3.62126264 0.0 0.0 0.0 3.62126264 0.0 0.0 0.0 3.62126264" Properties=species:S:1:pos:R:3:tags:I:1 spacegroup="F m -3 m" unit_cell=conventional pbc="T T T" Cu 0.00000000 0.00000000 0.00000000 0 Cu 1.81063132 1.81063132 0.00000000 0 Cu 1.81063132 0.00000000 1.81063132 0 Cu 0.00000000 1.81063132 1.81063132 0 </div></code></div><div> </div><div>Use the above XYZ file (converted from CIF taken from Materials Project) and the input below. This should converge to roughly VASP criteria in a few optimization steps. </div><div> </div><div><div style="background-color: rgb(250, 250, 250); border-color: rgb(187, 187, 187); border-style: solid; border-width: 1px; overflow-wrap: break-word;" class="prettyprint"><code class="prettyprint"><div class="subprettyprint">&GLOBAL PRINT_LEVEL LOW PROJECT_NAME Cu_mp-30_conventional_standard RUN_TYPE CELL_OPT EXTENDED_FFT_LENGTHS .TRUE. FFTW_PLAN_TYPE ESTIMATE PREFERRED_FFT_LIBRARY FFTW3 &TIMINGS SILENT THRESHOLD 1e-08 &END TIMINGS &END GLOBAL &MOTION &CELL_OPT KEEP_ANGLES .TRUE. EXTERNAL_PRESSURE 1 0 0 0 1 0 0 0 1 PRESSURE_TOLERANCE 1e1 MAX_ITER 400 OPTIMIZER BFGS MAX_DR 5e-04 &END CELL_OPT &PRINT &TRAJECTORY FORMAT XYZ &END TRAJECTORY &END PRINT &END MOTION &FORCE_EVAL METHOD QUICKSTEP STRESS_TENSOR ANALYTICAL &DFT UKS T CHARGE 0 MULTIPLICITY 1 BASIS_SET_FILE_NAME data/BASIS_MOLOPT POTENTIAL_FILE_NAME data/POTENTIAL WFN_RESTART_FILE_NAME Cu_mp-30_conventional_standard-RESTART.kp &MGRID CUTOFF 800 NGRIDS 5 RELATIVE_CUTOFF 50 &END MGRID &QS EPS_DEFAULT 1.0E-12 METHOD GPW EXTRAPOLATION USE_GUESS &END QS &SCF EPS_SCF 1e-06 MAX_SCF 200 SCF_GUESS RESTART ADDED_MOS 200 &OUTER_SCF F EPS_SCF 1e-06 MAX_SCF 20 &END OUTER_SCF &SMEAR T METHOD FERMI_DIRAC ELECTRONIC_TEMPERATURE 3.0000000000000000E+02 &END SMEAR &MIXING T METHOD BROYDEN_MIXING ALPHA 4.0000000000000002E-01 BETA 1.5000000000000000E+00 NMIXING 5 NBUFFER 8 &END MIXING &END SCF &XC FUNCTIONAL_ROUTINE NEW DENSITY_CUTOFF 1.0e-12 GRADIENT_CUTOFF 1.0e-12 TAU_CUTOFF 1.0e-12 &XC_FUNCTIONAL &PBE PARAMETRIZATION Orig &END PBE &END XC_FUNCTIONAL &XC_GRID USE_FINER_GRID T &END XC_GRID &END XC &POISSON POISSON_SOLVER PERIODIC PERIODIC XYZ &END POISSON &KPOINTS SCHEME MONKHORST-PACK 8 8 8 FULL_GRID .TRUE. &END KPOINTS &END DFT &SUBSYS &CELL ABC 3.621263 3.621263 3.621263 ALPHA_BETA_GAMMA 90.000000 90.000000 90.000000 PERIODIC XYZ &END CELL &KIND Cu BASIS_SET DZVP-MOLOPT-SR-GTH POTENTIAL GTH-PBE-q11 &END KIND &TOPOLOGY COORD_FILE_FORMAT XYZ COORD_FILE_NAME Cu_mp-30_conventional_standard.xyz CONN_FILE_FORMAT off &END TOPOLOGY &END SUBSYS &END FORCE_EVAL </div></code></div> </div> On Thursday, August 15, 2019 at 3:35:17 PM UTC-3, Hasan Al-Mahayni wrote:<blockquote class="gmail_quote" style="margin: 0;margin-left: 0.8ex;border-left: 1px #ccc solid;padding-left: 1ex;"><div dir="ltr">Hi,<div> </div><div>Thanks for your reply, I tried both methods. </div><div>1) For the Kpoint method, I get the following error: "GEOMETRY wrong or EMAX_SPLINE too small!"</div><div>2)For MULTIPLE_UNIT_CELL what should I write after it (the "X Y Z" section)? Should I start with 2 2 2? Also, do I put the same thing in both TOPOLOGY and CELL section? I tried 2 2 2, and I get ' Cholesky decompose failed: the matrix is not positive definite or ill-conditioned"</div><div> </div><div>Thanks,</div><div>Hasan.</div> <div> On Wednesday, August 14, 2019 at 8:25:15 PM UTC-4, Hasan Al-Mahayni wrote:<blockquote class="gmail_quote" style="margin:0;margin-left:0.8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Hello all,<div> </div><div>I am fairly new to cp2k so I believe this issue is easily resolvable. My end goal is calculating adsorption energy of different molecules on copper surfaces (slab). However, the first step I need to do is optimize the cell parameters of copper(cell size). I know from materials project site that it is 3.62126 Angstroms. That is the configuration I start with and is attached by the name of "<a href="http://copper.xyz" rel="nofollow" target="_blank" onmousedown="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fcopper.xyz\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNHf9SERQqffjEa9U8Yw-7d0xjTQNg';return true;" onclick="this.href='http://www.google.com/url?q\x3dhttp%3A%2F%2Fcopper.xyz\x26sa\x3dD\x26sntz\x3d1\x26usg\x3dAFQjCNHf9SERQqffjEa9U8Yw-7d0xjTQNg';return true;">copper.xyz</a>". The problem I am having is that when I run cell optimization on this (input file is "copper.inp"), I get the wrong results as the cell size shrinks (I get 3.4A). I think this is because of the vacuum between the copper cell and the simulation cell. My question is, what is the right way to set up the input file and especially the &CELL part. I started off by making the A B C cell size 10 A bigger than 3.62A, but that gives me the wrong result. If the A B C cell size is too small, I get an error saying geometry is wrong. Also, maybe GEO_OPT would be a more appropriate run type... I tried making supercell 2x2x2, 3x3x3, and 4x4x4 while keeping ABC cell size 10 A bigger every time, and the result gets closer to 3.62 but this method is not ideal as the system gets bigger and bigger and the calculation is more computationally expensive. Any ideas?</div><div> </div><div>Thanks,</div><div> </div><div>Hasan.</div> </div></blockquote></div></div></blockquote></div>