Dear Geng<div>You can set a restraint through</div><div><a href="https://manual.cp2k.org/trunk/CP2K_INPUT.html">CP2K_INPUT</a> / <a href="https://manual.cp2k.org/trunk/CP2K_INPUT/MOTION.html">MOTION</a> / <a href="https://manual.cp2k.org/trunk/CP2K_INPUT/MOTION/CONSTRAINT.html">CONSTRAINT</a> / <a href="https://manual.cp2k.org/trunk/CP2K_INPUT/MOTION/CONSTRAINT/COLLECTIVE.html">COLLECTIVE</a><br></div><div>The collective variable describing the bond you want to preserve has do be defined as a distance in </div><div><a href="https://manual.cp2k.org/trunk/CP2K_INPUT.html">CP2K_INPUT</a> / <a href="https://manual.cp2k.org/trunk/CP2K_INPUT/FORCE_EVAL.html">FORCE_EVAL</a> / <a href="https://manual.cp2k.org/trunk/CP2K_INPUT/FORCE_EVAL/SUBSYS.html">SUBSYS</a> / <a href="https://manual.cp2k.org/trunk/CP2K_INPUT/FORCE_EVAL/SUBSYS/COLVAR.html">COLVAR</a><br></div><div><br></div><div>Regards</div><div>Marcella</div><div><br><br></div><div class="gmail_quote"><div dir="auto" class="gmail_attr">On Saturday, January 29, 2022 at 2:49:32 AM UTC+1 Geng wrote:<br/></div><blockquote class="gmail_quote" style="margin: 0 0 0 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div>Dear CP2k users,</div><div>I wonder how to add an external force field on selected pairs of atoms (such as spring forces), so I can preserve the bond between atoms.?</div><div>Thank you very much in advance.<br>Best <br>Geng<br></div></blockquote></div>

<p></p>

-- <br />
You received this message because you are subscribed to the Google Groups "cp2k" group.<br />
To unsubscribe from this group and stop receiving emails from it, send an email to <a href="mailto:cp2k+unsubscribe@googlegroups.com">cp2k+unsubscribe@googlegroups.com</a>.<br />
To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/43280fce-39f1-4206-b153-07e5f6a492f4n%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/43280fce-39f1-4206-b153-07e5f6a492f4n%40googlegroups.com</a>.<br />