<div dir="ltr">Hi, <div>I have an issue with diverging SCF wavefunction optimization for 5 different systems of silicon nanocrystals with various ligands. So far this has not occurred (I have successfully simulated 20 other silicon nanocrystals with quite complicated ligands), so it does not seem to be consistent issue... </div><div><br></div><div>For silicon nanocrystal with 235 atoms in the core and surface covered with Sulfur I use these parameters (extract from cp2k.out for energy_force):</div><div><br></div><div><div><font color="#0000ff">SCF PARAMETERS </font></div><div><font color="#0000ff"> Density guess: RESTART</font></div><div><font color="#0000ff"> --------------------------------------------------------</font></div><div><font color="#0000ff"> max_scf: 200</font></div><div><font color="#0000ff"> max_scf_history: 0</font></div><div><font color="#0000ff"> max_diis: 4</font></div><div><font color="#0000ff"> --------------------------------------------------------</font></div><div><font color="#0000ff"> eps_scf: 5.00E-04</font></div><div><font color="#0000ff"> eps_scf_history: 0.00E+00</font></div><div><font color="#0000ff"> eps_diis: 1.00E-01</font></div><div><font color="#0000ff"> eps_eigval: 1.00E-05</font></div><div><font color="#0000ff"> --------------------------------------------------------</font></div><div><font color="#0000ff"> level_shift [a.u.]: 0.00</font></div><div><font color="#0000ff"> added MOs 100 0</font></div><div><font color="#0000ff"> --------------------------------------------------------</font></div><div><font color="#0000ff"> Mixing method: DIRECT_P_MIXING</font></div><div><font color="#0000ff"> --------------------------------------------------------</font></div><div><font color="#0000ff"> No outer SCF</font></div><div><br></div><div><font color="#0000ff">Number of electrons: 1780<br></font></div><div><font color="#0000ff"> Number of occupied orbitals: 890</font></div><div><font color="#0000ff"> Number of molecular orbitals: 4875</font></div><div><font color="#0000ff"><br></font></div><div><font color="#0000ff"> Number of orbital functions: 4875</font></div><div><font color="#0000ff"> Number of independent orbital functions: 4875</font></div><div><font color="#0000ff"><br></font></div><div><font color="#0000ff"> Extrapolation method: initial_guess</font></div><div><br></div><div>and I get this divergence in the optimization already after 2nd step:</div><div><br></div><div><font color="#ff0000"> SCF WAVEFUNCTION OPTIMIZATION</font></div><div><font color="#ff0000"><br></font></div><div><font color="#ff0000"> Step Update method Time Convergence Total energy Change</font></div><div><font color="#ff0000"> ------------------------------------------------------------------------------</font></div><div><font color="#ff0000"> 1 P_Mix/Diag. 0.40E+00 4.2 0.10908716 -2354.4136559975 -2.35E+03</font></div><div><font color="#ff0000"> 2 P_Mix/Diag. 0.40E+00 5.0 0.44462605 -2354.4126056799 1.05E-03</font></div><div><font color="#ff0000"> 3 P_Mix/Diag. 0.40E+00 5.1 0.53885704 -2354.3562265414 5.64E-02</font></div><div><font color="#ff0000"> 4 P_Mix/Diag. 0.40E+00 5.0 3.07899832 -2352.5424379413 1.81E+00</font></div><div><font color="#ff0000"> 5 P_Mix/Diag. 0.40E+00 5.0 33.29887563 -1891.1308608487 4.61E+02</font></div><div><font color="#ff0000"> 6 P_Mix/Diag. 0.40E+00 5.3 30.17765973 4133.1886655512 6.02E+03</font></div><div><font color="#ff0000"> 7 P_Mix/Diag. 0.40E+00 5.1 32.02311479 3797.3039280923 -3.36E+02</font></div><div><font color="#ff0000"> 8 P_Mix/Diag. 0.40E+00 5.1 31.83587407 1215.6949983041 -2.58E+03</font></div><div><font color="#ff0000"> 9 P_Mix/Diag. 0.40E+00 5.1 33.45037356 4635.2206528830 3.42E+03</font></div><div><font color="#ff0000"> 10 P_Mix/Diag. 0.40E+00 5.1 30.96157640 2861.7052141337 -1.77E+03</font></div><div><font color="#ff0000"> 11 P_Mix/Diag. 0.40E+00 5.1 29.36705839 2709.3853227498 -1.52E+02</font></div><div><font color="#ff0000"> 12 P_Mix/Diag. 0.40E+00 5.5 31.13837241 3593.9217491598 8.85E+02</font></div><div><font color="#ff0000"> 13 P_Mix/Diag. 0.40E+00 5.1 34.63292667 4412.8333731638 8.19E+02</font></div><div><font color="#ff0000"> 14 P_Mix/Diag. 0.40E+00 5.1 30.85152040 4458.1077941490 4.53E+01</font></div></div><div><font color="#ff0000">.......</font></div><div><div> <font color="#ff0000">Leaving inner SCF loop after reaching 200 steps.</font></div><div><font color="#ff0000"><br></font></div><div><font color="#ff0000"><br></font></div><div><font color="#ff0000"> Electronic density on regular grids: -1779.9999999908 0.0000000092</font></div><div><font color="#ff0000"> Core density on regular grids: 1779.9999997505 -0.0000002495</font></div><div><font color="#ff0000"> Total charge density on r-space grids: -0.0000002402</font></div><div><font color="#ff0000"> Total charge density g-space grids: -0.0000002402</font></div><div><font color="#ff0000"><br></font></div><div><font color="#ff0000"> Overlap energy of the core charge distribution: 0.00000002843702</font></div><div><font color="#ff0000"> Self energy of the core charge distribution: -5795.76572189967919</font></div><div><font color="#ff0000"> Core Hamiltonian energy: 2938.96179612088508</font></div><div><font color="#ff0000"> Hartree energy: 7673.11151856082142</font></div><div><font color="#ff0000"> Exchange-correlation energy: -640.40137237794443</font></div><div><font color="#ff0000"><br></font></div><div><font color="#ff0000"> Total energy: 4175.90622043252006</font></div><div><font color="#ff0000"><br></font></div><div><font color="#ff0000"> *** WARNING in qs_scf.F:479 :: SCF run NOT converged ***</font></div><div><font color="#ff0000"><br></font></div><div><font color="#ff0000"><br></font></div><div><font color="#ff0000"> ENERGY| Total FORCE_EVAL ( QS ) energy (a.u.): 55520.780056994452025</font></div></div><div><br></div><div>But the system is fully relaxed, so the SCF run converged before (for the GEO_OPT) - see below the relaxation cp2k.out extract:<br></div><div><br></div><div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff">-------- Informations at step = 25 ------------</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Optimization Method = CG</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Total Energy = -2354.4137112872</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Real energy change = -0.0000012787</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Decrease in energy = YES</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Used time = 475.723</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Convergence check :</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Max. step size = 0.0023939758</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Conv. limit for step size = 0.0030000000</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Convergence in step size = YES</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> RMS step size = 0.0003373842</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Conv. limit for RMS step = 0.0015000000</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Convergence in RMS step = YES</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Max. gradient = 0.0004156999</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Conv. limit for gradients = 0.0004500000</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Conv. in gradients = YES</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> RMS gradient = 0.0000585848</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Conv. limit for RMS grad. = 0.0003000000</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Conv. in RMS gradients = YES</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> ---------------------------------------------------</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> *******************************************************************************</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> *** GEOMETRY OPTIMIZATION COMPLETED ***</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> *******************************************************************************</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Reevaluating energy at the minimum</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Number of electrons: 1780</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Number of occupied orbitals: 890</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Number of molecular orbitals: 890</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Number of orbital functions: 4875</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Number of independent orbital functions: 4875</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Extrapolation method: ASPC</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> SCF WAVEFUNCTION OPTIMIZATION</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> ----------------------------------- OT ---------------------------------------</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Minimizer : DIIS : direct inversion</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> in the iterative subspace</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> using 7 DIIS vectors</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> safer DIIS on</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Preconditioner : FULL_KINETIC : inversion of T + eS</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Precond_solver : DEFAULT</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> stepsize : 0.15000000 energy_gap : 0.20000000</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> eps_taylor : 0.10000E-15 max_taylor : 4</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> ----------------------------------- OT ---------------------------------------</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Step Update method Time Convergence Total energy Change</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> ------------------------------------------------------------------------------</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> 1 OT DIIS 0.15E+00 3.5 0.00000227 -2354.4136673140 -2.35E+03</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> 2 OT DIIS 0.15E+00 4.2 0.00000210 -2354.4136705162 -3.20E-06</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> 3 OT DIIS 0.15E+00 4.1 0.00000166 -2354.4136799605 -9.44E-06</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> 4 OT DIIS 0.15E+00 4.1 0.00000127 -2354.4136892114 -9.25E-06</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> 5 OT DIIS 0.15E+00 4.1 0.00000111 -2354.4136936860 -4.47E-06</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> 6 OT DIIS 0.15E+00 4.1 0.00000103 -2354.4136965337 -2.85E-06</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> 7 OT DIIS 0.15E+00 4.1 0.00000092 -2354.4137006183 -4.08E-06</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> *** SCF run converged in 7 steps ***</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Electronic density on regular grids: -1779.9999999998 0.0000000002</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Core density on regular grids: 1779.9999997509 -0.0000002491</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Total charge density on r-space grids: -0.0000002490</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Total charge density g-space grids: -0.0000002490</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Overlap energy of the core charge distribution: 0.00000002843702</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Self energy of the core charge distribution: -5795.76572189967919</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Core Hamiltonian energy: 1266.52936221037999</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Hartree energy: 2771.64162064259563</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Exchange-correlation energy: -596.81896159999383</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> Total energy: -2354.41370061826001</font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"> ENERGY| Total FORCE_EVAL ( QS ) energy (a.u.): -2354.413700618260009</font></span></div></div><div><span style="background-color: rgb(255, 255, 255);"><font color="#ff00ff"><br></font></span></div><div><div>Please, anyone has an idea what am I doing wrong? </div></div><div><br></div><div>Thank you in advance for any advice... </div><div><br></div><div>best regards</div><div><br></div><div>Katerina (Uni Amsterdam, NL)</div></div>