<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; color: rgb(0, 0, 0); font-size: 14px; font-family: Calibri, sans-serif; "><div> I am running cpmd simulations with quantum espresso.</div><div> I would like to run with restraints on two atoms, ie adding a harmonic force constant to their separation distance.</div><div>I would prefer this to the CONSTRAINTS option. </div><div>The RESTRAINTS option is present with the original cpmd code (ie from cpmd.org). </div><div>Is there a RESTRAINTS option with quantum espresso?</div><div><br></div><div>Phil Kiefer</div></body></html>