<html><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:10pt"><div>Dear user QE.</div><div><br></div><div>I'm using cp.x to perform molecular dynamics of one of bulk water molecules with asparagine.</div><div>Following protocol, I minimized the function of wave electronics with stationary nuclei.</div><div><br></div><div>However, in the second stage, during the optimization of the geometry (with damp for electrons and ions) </div><div>the water molecules take a non-real geometry, in which one side of the molecule, the OH distance becomes 1.98 angstrorn (A).</div><div>The opposite side, has the normal size of the bond which is 0.97 A. I confess that since I started using it very often, </div><div>and sometimes does not, but do not know why that. Sometimes change is functional and that resolved, sometimes
not.</div><div><br></div><div><br></div><div><br></div><div>Incoherent bond distances of water after geometry optmization >>>>> H------------------O -----------H</div><div>(sorry by bad graphic) | 1.98 A| |0.97 A|</div><div><br></div><div><br></div><div>Can someone help me? </div><div>Put my input to be analyzed.</div><div><br></div><div style="color: rgb(0, 0, 0); font-size: 13.600000381469727px; font-family: HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif; background-color: transparent; font-style: normal;"><br></div><div>&CONTROL</div><div> title = 'Asp0s'</div><div>
calculation = 'cp',</div><div> restart_mode = 'restart',</div><div> ndr = 51 !already minimized wf with sd for electrons and ions=none.</div><div> ndw = 52, </div><div> nstep = 50000,</div><div> iprint = 1, </div><div> isave = 10,</div><div> tstress = .TRUE.,</div><div> tprnfor = .TRUE.,</div><div> dt = 5.0d0,</div><div> etot_conv_thr = 1.d-8,</div><div> ekin_conv_thr = 1.d-4,</div><div> forc_conv_thr = 1.d-4,</div><div> prefix = 'asp'</div><div> pseudo_dir = 'pseudo/'</div><div> outdir = './'</div><div>/</div><div><br></div><div>&SYSTEM</div><div> ibrav = 1, </div><div> celldm(1) = 20, </div><div> celldm(2) = 0.0, </div><div> celldm(3) = 0.0, </div><div> celldm(4) = 0.0, </div><div> celldm(5) = 0.0, </div><div> celldm(6) =
0.0, </div><div> nat = 122,</div><div> ntyp = 4,</div><div> ecutwfc = 70.0,</div><div>/</div><div><br></div><div>&ELECTRONS</div><div> emass = 400.d0,</div><div> emass_cutoff = 2.5d0,</div><div> orthogonalization = 'ortho',</div><div> electron_dynamics = 'damp',</div><div> electron_damping = 0.1</div><div> ortho_max = 500,</div><div> !electron_temperature = 'not_controlled',</div><div> !electron_velocities = 'zero'</div><div>/</div><div><br></div><div>&IONS</div><div> ion_dynamics = 'damp',</div><div> ion_damping = 0.01,</div><div> !ion_nstepe = 10,</div><div> !ion_temperature = 'nose',</div><div> !tempw = 350,</div><div> !fnosep = 70,</div><div> !ion_velocities = 'zero'</div><div>/</div><div><br></div><div><br></div><div>ATOMIC_SPECIES</div><div><br></div><div> O 16.0d0 O.pbe-hgh.UPF</div><div> H 1.0d0
H.pbe-hgh.UPF </div><div> C 12.0d0 C.pbe-hgh.UPF </div><div> N 14.0d0 N.pbe-hgh.UPF</div><div><br></div><div>ATOMIC_POSITIONS {angstrom}</div><div><br></div><div> C -0.244144 1.783022 -1.335832 </div><div> C -2.567204 -0.241389 5.783803 </div><div> N -1.038197 -1.652589 5.418683 </div><div> C -6.336078 -1.532299 -1.532562 </div><div> O -5.122808 -0.424258 -2.279843 </div><div> N 3.987336 0.412822 -1.692063 </div><div> C 0.552282 -0.043486 0.368085 </div><div> O 1.73575
0.043368 0.476670 </div><div> O 1.126133 -1.181319 1.757325 </div><div> H -0.844512 -1.781630 -0.580034 </div><div> H -1.992345 -1.968023 0.581635 </div><div> H -1.547999 -0.018973 1.618910 </div><div> H -1.017864 1.793541 0.067225 </div><div> H -2.180408 0.669590 -0.675764 </div><div> H 1.490782 1.185685 -2.387313 </div><div> H 1.070763 1.992771 -0.909308 </div><div> H 0.490233 -1.888235
1.458829 </div><div> O 5.160929 1.400891 -4.018523 </div><div> H 5.585303 1.845186 -4.767840 </div><div> H 5.903707 1.074826 -3.488501 </div><div> O 6.523016 -2.630620 -1.333026 </div><div> H 6.731773 -1.730291 -1.624223 </div><div> H 6.238875 -2.519196 -0.413345 </div><div>( ........)</div><div><br></div><div><br></div><div><div style="margin-top: 0.1em; margin-bottom: 0.1em; background-color: transparent;">Alex.</div><div style="margin-top: 0.1em; margin-bottom: 0.1em;">Thanks to all.</div></div></div></body></html>