<div dir="ltr"><div>OK, thaks, this is the MD section:</div><div><br><div><b>&MOTION</b></div><div><b>&MD</b></div><div><b><br></b></div><div><b>&VELOCITY_SOFTENING</b></div><div><b>STEPS 30</b></div><div><b>ALPHA 0.2</b></div><div><b>DELTA 0.05</b></div><div><b>&END</b></div><div><b><br></b></div><div><b>DISPLACEMENT_TOL 40</b></div><div><b>ENSEMBLE NVT</b></div><div><b>STEPS 30000</b></div><div><b>TIMESTEP 0.5</b></div><div><b>TEMPERATURE 300</b></div><div><b>&THERMOSTAT</b></div><div><b>REGION GLOBAL</b></div><div><b>TYPE CSVR</b></div><div><b>#&NOSE</b></div><div><b>#LENGTH 6</b></div><div><b>#YOSHIDA 3</b></div><div><b>#MTS 2</b></div><div><b>#TIMECON 0.5</b></div><div><b>#&END NOSE</b></div><div><b>&CSVR</b></div><div><b>TIMECON 1</b></div><div><b>&END CSVR</b></div><div><b>&END THERMOSTAT</b></div><div><b><br></b></div><div><b>&PRINT</b></div><div><b>&ENERGY</b></div><div><b>&EACH</b></div></div><div><b><div>MD 1 </div><div>&END </div><div>ADD_LAST NUMERIC </div><div>&END </div><div>&END PRINT </div><div>&END MD </div><div> </div><div>&PRINT <b><div style="display:inline!important"><b><div style="display:inline!important"><b><div style="display:inline!important"> </div></b></div></b></div></b><b><div style="display:inline!important"> </div></b><b><div style="display: inline !important;">&TRAJECTORY ON </div></b></div><div>FILENAME ./Au_300K </div><div>FORMAT XYZ </div><div>&EACH </div><div>MD 2 </div><div>&END EACH </div><div>&END TRAJECTORY </div><div>&END PRINT </div><div>&END MOTION</div></b></div><div><br></div><font color="#ff0000">As you can see, the program output the trajectories every two MD steps (every 1 fs)</font><br><br>在 2016年11月10日星期四 UTC+8下午5:09:01，Vladimir Rybkin写道：<blockquote class="gmail_quote" style="margin:0;margin-left:0.8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Dear author,<br><br>Generally, the particle will travel 0.4 angstrom in 1 fs if no forces act on it (Newton's first law). In genaral, in atomistic systems the forces are not zero.<br>what was you time step? Could you provide the whole input (at least $subsys and $MD)?<br><br>Yours,<br><br>Vladimir<br><br>четверг, 10 ноября 2016 г., 9:38:23 UTC+1 пользователь <a>zhj...@gmail.com</a> написал:<blockquote class="gmail_quote" style="margin:0;margin-left:0.8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">Hi, all<div>In MD simulation, I give an Au particle the velocity of 0.42 angstrom*fs^-1 by using <a href="https://manual.cp2k.org/cp2k-4_1-branch/CP2K_INPUT.html" style="font-family:monospace;text-transform:uppercase" rel="nofollow" target="_blank">CP2K_INPUT</a><span style="color:rgb(0,0,0);font-family:monospace;text-transform:uppercase"> / </span><a href="https://manual.cp2k.org/cp2k-4_1-branch/CP2K_INPUT/FORCE_EVAL.html" style="font-family:monospace;text-transform:uppercase" rel="nofollow" target="_blank">FORCE_EVAL</a><span style="color:rgb(0,0,0);font-family:monospace;text-transform:uppercase"> <wbr>/ </span><a href="https://manual.cp2k.org/cp2k-4_1-branch/CP2K_INPUT/FORCE_EVAL/SUBSYS.html" style="font-family:monospace;text-transform:uppercase" rel="nofollow" target="_blank">SUBSYS</a><span style="color:rgb(0,0,0);font-family:monospace;text-transform:uppercase"> / </span><a href="https://manual.cp2k.org/cp2k-4_1-branch/CP2K_INPUT/FORCE_EVAL/SUBSYS/VELOCITY.html" style="font-family:monospace;text-transform:uppercase" rel="nofollow" target="_blank">VELOCITY</a> . However, when I visualize the results, I found that this Au particle traveled a distance of about 4 angstrom in 1 fs.</div><div>So, can anyone tell me the reason?</div><div><br></div><div><br></div><div>Here, I post the parts of velocity setting:</div><div><br></div><div>......</div><div><div>&VELOCITY</div><div>PINT_UNIT angstrom*fs^-1</div><div>0 0 0 </div><div>0 0 0 </div><div>0 0 0 </div><div>0 0 0 </div><div>0 0 0 </div><div>0 0 0 </div></div><div>......</div><div>......</div><div><div>0 0 0 </div><div>0 0 0</div></div><div><div><font color="#0000ff">0 0 -0.41989 ## this is the velocity of Au particle</font></div><div>&END VELOCITY</div></div></div></blockquote></div></blockquote></div>