<div><div style="   ;;  ">Dear all,</div><div style="   ;;  "><br></div><div style="   ;;  "><span class="fontstyle0">I have designed a model with </span><span class="fontstyle0"><span class="fontstyle0">two self-mated Fe(110) surfaces</span>.  </span><span class="fontstyle0"><span class="fontstyle0">During the </span></span><span class="fontstyle0"><span class="fontstyle0"><span class="fontstyle0">dynamic</span> 
simulations</span>,the bottom layer of the lower slab (the substrate) 
was held rigid, while the upper slab (the counter-surface) was moved at 
constant velocity.</span></div><div style="   ;;  "><span class="fontstyle0"><br></span></div><div style="   ;;  "><span class="fontstyle0">How can I apply constant velocity such as 200m/s along the y direction on the upper atoms through the whole progress  </span><span class="fontstyle0">using cp.x in <span style="white-space: pre-wrap; font-family: Verdana, sans-serif;" lang="EN-US">Quantum Espresso 6.1. version</span><span style="font-family: monospace; white-space: pre-wrap;" lang="EN-US"><font style="line-height: 23.8px;" face="courier, courier new, monospace"> </font></span><span style="white-space: pre-wrap; font-family: Verdana, sans-serif;" lang="EN-US"></span>.</span><br style=" font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div><span style="white-space: pre-wrap;"><br></span></div><div><span style="white-space: pre-wrap;">Any help would be appreciated.</span></div><div><br></div></div><div style="   ;;  "><pre style="line-height: 23.8px; margin-top: 0px; margin-bottom: 0px;"><div style="font-family: Verdana; white-space: normal;"><div>Thank you!</div><div>Best regards,</div></div><div style="font-family: Verdana; white-space: normal;"><br></div><div style="font-family: Verdana; white-space: normal;">------</div><div style="font-family: Verdana; white-space: normal;"><p class="MsoNormal" style="line-height: 17.85pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;" align="left"><span lang="EN-US">LU Hailin, Graduate Student</span><span style="font-family: Verdana, sans-serif;" lang="EN-US"></span></p><p class="MsoNormal" style="line-height: 17.85pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;" align="left"><span lang="EN-US">State Key Laboratory of Mechanical Transmission, Chongqing University</span><span style="font-family: Verdana, sans-serif;" lang="EN-US"></span></p><p class="MsoNormal" style="line-height: 17.85pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;" align="left"><span lang="EN-US">Chongqing 400044, China</span></p><p class="MsoNormal" style="line-height: 17.85pt; background-image: initial; background-position: initial; background-size: initial; background-repeat: initial; background-attachment: initial; background-origin: initial; background-clip: initial;" align="left"><span lang="EN-US">Tel: (+86) 18362360286</span></p></div></pre></div></div>