<div>Hi all,</div><div>I am working on surface diffusion of a single water molecule on Pd(111) at a given temperature (50K) by using molecular dynamics in pw.x. However, the output file shows that the system temperature continuously goes down. I am not sure whether I used correct parameters in the input to fix the target temperature. Is something wrong with my input file? What's the correct way to simulate the surface diffusion at a given temperature? </div><div><br></div><div>> grep 'temperature' bomd.pw.out<br> Starting temperature = 50.00 K<br> temperature is controlled by velocity rescaling (rescaling)<br> temperature = 50.00000000 K <br> temperature = 49.08451411 K <br> temperature = 47.34902025 K <br> temperature = 48.69776388 K <br> temperature = 48.67531303 K <br> temperature = 48.13806887 K <br> temperature = 47.77128183 K <br> temperature = 48.84955608 K <br> temperature = 49.99377244 K <br> temperature = 49.46353472 K <br> temperature = 48.20956748 K <br> temperature = 48.50820119 K <br> temperature = 48.74058134 K <br> temperature = 48.08050314 K <br> temperature = 46.19882695 K <br> temperature = 45.34486798 K <br> temperature = 46.04136511 K <br> temperature = 46.51546894 K <br> temperature = 45.64423710 K <br> temperature = 44.80023560 K <br></div><div><br></div><div><br></div><div>INPUT FILE<br></div><div> &CONTROL<br> calculation = 'md' ,<br> restart_mode = 'from_scratch' ,<br> outdir = './' ,<br> pseudo_dir = '/home/jibiaoli/pseudo/' ,<br> prefix = 'bomd' ,<br> nstep = 200 ,<br> tstress = .true. ,<br> tprnfor = .true. ,<br> dt = 50 ,<br> /<br> &SYSTEM<br> ibrav = 8,<br> celldm(1) = 15.596671813,<br> celldm(2) = 1.154699881261,<br> celldm(3) = 2.876257,<br> nat = 51,<br> ntyp = 3,<br> ecutwfc = 49 ,<br> ecutrho = 411 ,<br> occupations = 'smearing' ,<br> degauss = 0.05D0 ,<br> smearing = 'methfessel-paxton' ,<br> vdw_corr = 'grimme-d2' ,<br> /<br> &ELECTRONS<br> mixing_beta = 0.2D0 ,<br> diagonalization = 'david' ,<br> /<br> &IONS<br> ion_dynamics = 'verlet' ,<br> ion_temperature = 'rescaling' ,<br> tempw = 50 ,<br> tolp = 1 ,<br> delta_t = 1 ,<br> nraise = 1 ,<br> /<br>ATOMIC_SPECIES<br> O 15.99900 O.pbe-n-kjpaw_psl.1.0.0.UPF <br> H 1.00790 H.pbe-kjpaw_psl.1.0.0.UPF <br> Pd 106.40000 Pd.pbe-n-kjpaw_psl.1.0.0.UPF <br>ATOMIC_POSITIONS angstrom <br> H 3.749292613 5.567569316 9.134421266 <br> H 3.803720062 4.024397884 9.087662377 <br> O 3.173832077 4.774393547 9.142099838 <br></div><div> Pd -0.015321105 9.523398271 6.774164621 <br> Pd 2.722844638 4.758595557 6.785562209 <br> Pd 5.490883134 9.523895908 6.777071069 <br> Pd 8.228806411 4.758298844 6.770864880 <br> Pd 1.356930947 2.368010181 6.769560450 <br> Pd 4.119325735 7.149818888 6.768390428 <br> Pd 6.862178456 2.372021282 6.778917989 <br> Pd 2.738593954 9.523860670 6.777549970 <br> Pd 5.494886254 4.759214643 6.766979210 <br> Pd 1.358442938 7.149196831 6.769444322 <br> Pd 4.118144062 2.368040151 6.768758108 <br> Pd 6.862965497 7.145267601 6.777586390 <br> Pd 0.000000000 6.353486495 4.492593385 0 0 0 <br> Pd 2.751140354 1.588371624 4.492593385 0 0 0 <br> Pd 5.502280707 6.353486495 4.492593385 0 0 0 <br> Pd 8.253421061 1.588371624 4.492593385 0 0 0 <br> Pd 1.375570177 8.736043930 4.492593385 0 0 0 <br> Pd 4.126710530 3.970929059 4.492593385 0 0 0 <br> Pd 6.877850884 8.736043930 4.492593385 0 0 0 <br> Pd 2.751140354 6.353486495 4.492593385 0 0 0 <br> Pd 5.502280707 1.588371624 4.492593385 0 0 0 <br> Pd 1.375570177 3.970929059 4.492593385 0 0 0 <br> Pd 4.126710530 8.736043930 4.492593385 0 0 0 <br> Pd 6.877850884 3.970929059 4.492593385 0 0 0 <br> Pd 0.000000000 3.176743247 2.246296693 0 0 0 <br> Pd 2.751140354 7.941858119 2.246296693 0 0 0 <br> Pd 5.502280707 3.176743247 2.246296693 0 0 0 <br> Pd 8.253421061 7.941858119 2.246296693 0 0 0 <br> Pd 1.375570177 5.559300683 2.246296693 0 0 0 <br> Pd 4.126710530 0.794185812 2.246296693 0 0 0 <br> Pd 6.877850884 5.559300683 2.246296693 0 0 0 <br> Pd 2.751140354 3.176743247 2.246296693 0 0 0 <br> Pd 5.502280707 7.941858119 2.246296693 0 0 0 <br> Pd 1.375570177 0.794185812 2.246296693 0 0 0 <br> Pd 4.126710530 5.559300683 2.246296693 0 0 0 <br> Pd 6.877850884 0.794185812 2.246296693 0 0 0 <br> Pd 0.000000000 9.530229742 0.000000000 0 0 0 <br> Pd 2.751140354 4.765114871 0.000000000 0 0 0 <br> Pd 5.502280707 9.530229742 0.000000000 0 0 0 <br> Pd 8.253421061 4.765114871 0.000000000 0 0 0 <br></div><div> Pd 1.375570177 2.382557436 0.000000000 0 0 0 <br> Pd 4.126710530 7.147672307 0.000000000 0 0 0 <br> Pd 6.877850884 2.382557436 0.000000000 0 0 0 <br> Pd 2.751140354 9.530229742 0.000000000 0 0 0 <br> Pd 5.502280707 4.765114871 0.000000000 0 0 0 <br> Pd 1.375570177 7.147672307 0.000000000 0 0 0 <br> Pd 4.126710530 2.382557436 0.000000000 0 0 0 <br> Pd 6.877850884 7.147672307 0.000000000 0 0 0 <br>K_POINTS automatic <br> 4 4 1 0 0 0 <br><br></div><div><div style="color:#909090;font-family:Arial Narrow;font-size:12px">------------------</div><div style="font-size:14px;font-family:Verdana;color:#000;"><div><i><font color="#0000ff" face="Times New Roman" size="2"><b>Dr. Jibiao Li, </b></font></i></div><div><i><font color="#0000ff" face="Times New Roman" size="2"><b>Department of Material Science and Engineering</b></font></i></div><div><i><font color="#0000ff" face="Times New Roman" size="2"><b>Yangtze Normal University</b></font></i></div><div><i><font face="Times New Roman"><font size="2"><font color="#0000ff"><b><span style="text-align: left; text-transform: none; line-height: 21px; text-indent: 0px; letter-spacing: normal; font-variant: normal; text-decoration: none; word-spacing: 0px; display: inline !important; white-space: normal; orphans: 2; float: none; -webkit-text-stroke-width: 0px; background-color: transparent;">Juxian Dadao 16#,</span> Fuling, Chongqing, China</b></font></font></font></i></div><div><i><font color="#0000ff" face="Times New Roman" size="2"><b>Email: jibiaoli@yznu.edu.cn, jibiaoli@foxmail.com, jibiao.li@hotmail.com</b></font></i></div><div><i><font color="#0000ff" face="Times New Roman" size="2"><b>Homepage: https://www.researchgate.net/profile/Jibiao_Li</b></font></i></div>
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