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<span style="color: rgb(33, 33, 33); font-family: sans-serif, serif, EmojiFont; font-size: 15px; background-color: rgb(255, 255, 255); display: inline !important">Dear Giuliana and QE users,</span><br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<span style="color: rgb(33, 33, 33); font-family: sans-serif, serif, EmojiFont; font-size: 15px; background-color: rgb(255, 255, 255); display: inline !important"><br>
</span></div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<span style="color: rgb(33, 33, 33); font-family: sans-serif, serif, EmojiFont; font-size: 15px; background-color: rgb(255, 255, 255); display: inline !important">Thanks very much for suggestions. I have read CPMD tutorials and followed it, but I still have
some problem.</span></div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<span style="color: rgb(33, 33, 33); font-family: sans-serif, serif, EmojiFont; font-size: 15px; background-color: rgb(255, 255, 255); display: inline !important"><br>
</span></div>
<div style=""><font color="#212121" face="sans-serif, serif, EmojiFont"><span style="font-size: 15px;">The following is my inputs</span></font></div>
<div style=""><font color="#212121" face="sans-serif, serif, EmojiFont"><span style="font-size: 15px;"><br>
</span></font></div>
<div style=""><font color="#212121" face="sans-serif, serif, EmojiFont"><span style="font-size: 15px;">1. Minimization </span></font></div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<span style="color: rgb(33, 33, 33); font-family: sans-serif, serif, EmojiFont; font-size: 15px; background-color: rgb(255, 255, 255); display: inline !important"><span><br>
</span>
<div>&CONTROL</div>
<div> etot_conv_thr = 3.5D-6 ,<br>
</div>
<div> forc_conv_thr = 4.0D-4 ,<br>
</div>
<div> ekin_conv_thr = 1d-9 ,</div>
<div> nstep = 20000 ,</div>
<div> dt=2.067,</div>
<div>/<br>
</div>
<div>&ELECTRONS<br>
</div>
<div> emass = 200<br>
</div>
<div> emass_cutoff = 2.50,<br>
</div>
<div> electron_dynamics = 'sd' ,<br>
</div>
<div> orthogonalization = 'ortho' , <br>
</div>
<div>/<br>
</div>
<div>&IONS<br>
</div>
<div> ion_dynamics = 'none', <br>
</div>
<div>/</div>
<div>ATOMIC_SPECIES<br>
</div>
<div> C 12.010700d0 C_pbe_v1.2.uspp.F.UPF<br>
</div>
<div> P 30.973800d0 P.pbe-n-rrkjus_psl.1.0.0.UPF<br>
</div>
<div><br>
</div>
<div>2. NVE</div>
<div><br>
</div>
<div>
<div>&CONTROL</div>
<div> etot_conv_thr = 3.5D-6 ,<br>
</div>
<div> forc_conv_thr = 4.0D-4 ,<br>
</div>
<div> ekin_conv_thr = 1d-9 ,</div>
<div> nstep = 20000 ,</div>
<div> dt=2.067,</div>
<div>/</div>
<div>&ELECTRONS<br>
</div>
<div> emass = 200<br>
</div>
<div> emass_cutoff = 2.50,<br>
</div>
<div> orthogonalization = 'ortho' , <br>
</div>
<div> electron_dynamics = 'verlet' ,<br>
</div>
<div> electron_velocities = 'zero' ,<br>
</div>
<div>/<br>
</div>
<div>&IONS<br>
</div>
<div> ion_dynamics = 'verlet',<br>
</div>
<div> ion_velocities = 'zero' ,<br>
</div>
<div>/</div>
<div>ATOMIC_SPECIES<br>
</div>
<div> C 12.010700d0 C_pbe_v1.2.uspp.F.UPF<br>
</div>
<div> P 30.973800d0 P.pbe-n-rrkjus_psl.1.0.0.UPF</div>
</div>
<div><br>
</div>
<div>3. 300 K NVT with thermostat</div>
<div> </div>
<div>
<div>&CONTROL</div>
<div> etot_conv_thr = 3.5D-6 ,<br>
</div>
<div> forc_conv_thr = 4.0D-4 ,<br>
</div>
<div> ekin_conv_thr = 1d-9 ,</div>
<div> nstep = 70000 ,<br>
</div>
<div> dt=4.134,</div>
<div>/<br>
</div>
<div><br>
</div>
<div>&ELECTRONS<br>
</div>
<div> emass = 200<br>
</div>
<div> emass_cutoff = 2.50,<br>
</div>
<div> electron_dynamics = 'verlet' ,<br>
</div>
<div> orthogonalization = 'ortho' , <br>
</div>
<div>/<br>
</div>
<div>&IONS<br>
</div>
<div> ion_dynamics = 'verlet',<br>
</div>
<div> tempw = 300 ,<br>
</div>
<div> ion_temperature = 'nose' ,<br>
</div>
<div> fnosep = 50 ,<br>
</div>
<div>/</div>
<div>ATOMIC_SPECIES<br>
</div>
<div> C 12.010700d0 C_pbe_v1.2.uspp.F.UPF<br>
</div>
<div> P 30.973800d0 P.pbe-n-rrkjus_psl.1.0.0.UPF<br>
</div>
<div><br>
</div>
</div>
<div>The results for NVT is following:</div>
<div><img size="29246" contenttype="image/png" unselectable="on" tabindex="-1" style="max-width: 100%; user-select: none;" data-outlook-trace="F:1|T:1" src="cid:754876fe-394a-43bc-9575-1471d33484f0"><br>
</div>
<div><br>
</div>
<div><img size="56470" contenttype="image/png" unselectable="on" tabindex="-1" style="max-width: 100%; user-select: none;" data-outlook-trace="F:1|T:1" src="cid:f7fd3e61-8ab6-48cc-8fbd-ab07dbdf9dfa"><br>
</div>
<div><img size="56027" contenttype="image/png" unselectable="on" tabindex="-1" style="max-width: 100%; user-select: none;" data-outlook-trace="F:1|T:1" src="cid:e650f4bd-b60e-4e5b-a62e-41b57c642427"><br>
</div>
<div>It is noted that the Ekinc is very small but it increased all the time.</div>
<div>The etot show a very slow growth.</div>
<div>Econs nearly keeps constants.</div>
<div><br>
</div>
<div>So, I am wondering how to get a constant Ekinc and Etot?</div>
<div><br>
</div>
<div>And how to determined the parameters，such as <span style="font-family: sans-serif, serif, EmojiFont; background-color: rgb(255, 255, 255); display: inline !important">emass and fnosep ?</span></div>
<div><span style="font-family: sans-serif, serif, EmojiFont; background-color: rgb(255, 255, 255); display: inline !important"><br>
</span></div>
<div><span style="font-family: sans-serif, serif, EmojiFont; background-color: rgb(255, 255, 255); display: inline !important">Thanks in advance.</span></div>
<div><span style="font-family: sans-serif, serif, EmojiFont; background-color: rgb(255, 255, 255); display: inline !important"><br>
</span></div>
<div>LIANG Xiongyi</div>
</span></div>
<div id="appendonsend"></div>
<div style="font-family:Calibri,Helvetica,sans-serif; font-size:12pt; color:rgb(0,0,0)">
CIty University of Hong Kong</div>
<hr tabindex="-1" style="display:inline-block; width:98%">
<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>发件人:</b> users <users-bounces@lists.quantum-espresso.org> 代表 Materzanini Giuliana <giuliana.materzanini@epfl.ch><br>
<b>发送时间:</b> 2019年1月18日 23:51<br>
<b>收件人:</b> Quantum Espresso users Forum<br>
<b>主题:</b> Re: [QE-users] 答复: Question on CPMD</font>
<div> </div>
</div>
<div>
<div dir="auto">
<div>
<div>
<div dir="auto" style="font-family:sans-serif"><br>
</div>
<div dir="auto" style="font-family:sans-serif">Dear Liang,<br>
<br>
yes, CPMD can run in NVT and also in NPH, NPT. But I would solve your problem in NVE first, and then play with NVT.<br>
<br>
In any case from your plots and inputs it is not hard to understand what's wrong in your calculations. </div>
<div dir="auto" style="font-family:sans-serif">Please also refer to this paper</div>
<div dir="auto" style="font-family:sans-serif"><br>
</div>
<div dir="auto" style="font-family:sans-serif"><span style="color:rgb(34 ,34 ,34); font-family:'arial' ,sans-serif; font-size:16px; font-style:italic; background-color:rgb(255 ,255 ,255)">Physical Review A 44 (10), 6334, 1991</span><br>
</div>
<div dir="auto" style="font-family:sans-serif"><span style="color:rgb(34 ,34 ,34); font-family:'arial' ,sans-serif; font-size:16px; font-style:italic; background-color:rgb(255 ,255 ,255)"><br>
</span></div>
<div dir="auto" style="font-family:sans-serif">in order to learn how the CP method works and what you should take care of.<br>
I try to explain you here quickly the meaning of the symbols in the file .evp you mentioned earlier, and the parameters to be tuned in your input.<br>
<br>
First of all you should know that:<br>
<br>
- Ekinc = kinetic energy of the coefficients of the electronic wavefunctions<br>
- Etot = total energy of the electrons (i.e. potential on which the ions move)<br>
- Econs = Etot + Ekin_ions = total energy of the whole real system (ions+electrons)<br>
- Econt = Etot + Ekin_ions + Ekinc = total energy of the whole fake system (i.e. real system + electronic wavefunctions)</div>
<div dir="auto" style="font-family:sans-serif"> (This holds in a NVE simulation. For NVT you would also have the contribution of the thermostat.)<br>
As Riccardo pointed out, Econt must be constant. Econs should oscillate around a constant.<br>
<br>
In the CP method you are propagating not only the ions, but also the electronic wavefunctions, that have a mass (emass) and a kinetic energy (ekinc). The mass is arbitrary - you decide. But if the mass is too big, the kinetic energy of the electronic wavefunctions
becomes too close to the one of the ions and the two systems will exchange energy, so that the kinetic energy of the electronic wavefunctions (ekinc) will grow again and again. This is exactly what is happening in your calculations: you have ekinc continuously
increasing. In a NVE simulation this means that T_ions (i.e. E_kin_ions) decreases, whereas this cannot happen in a NVT simulation, because you have a thermostat that keeps T_ions fixed.<br>
In any case, if E_kinc increases, E_cont increases, and your calculations are wrong as your constant of motion is not conserved.<br>
<br>
I see that your E_kin_ion (= E_cons - E_tot) is ~0.1eV and your starting ekinc is ~0.2eV !!! You have definitely a too high ekinc, and you should decrease emass. Go to emass = 300 au or even less, and check that ekinc < Ekin_ions. In general <br>
Ekinc < 1/10 Ekin_ions should be enough. Then you should take care that your timestep is not too high for this small mass, and possibly choose a shorter dt. A too large dt would cause again Econt to drift during your simulation.<br>
<br>
In summary:</div>
<div dir="auto" style="font-family:sans-serif">- read the paper above, or any good paper about the CP method.</div>
<div dir="auto" style="font-family:sans-serif">- run NVE first. Keep in mind that Econs - Etot = Ekin_ions. In NVE you also have that Econt = Econs + ekinc.</div>
<div dir="auto" style="font-family:sans-serif">- try several emass and dt, looking each time at:<br>
a) the comparison between ekinc and Ekin_ions (ekinc must be at least 1/10 of Ekin_ions)<br>
b) the conservation of Econt (and the oscillation of Econs around a constant): if Econt still grows, then choose a shorter timestep. Your plots should look like Riccardo's.<br>
<br>
Finally, please use a stricter threshold for eki<font color="#212121">nc: ekinc_conv_thr = 1d-4 is too high, I would rather go to 1d-9.</font></div>
<div dir="auto" style="font-family:sans-serif"><font color="#212121"><br>
</font></div>
<div dir="auto" style="font-family:sans-serif"><font color="#212121">Good luck!</font></div>
<div dir="auto" style="font-family:sans-serif"><br>
Giuliana<br>
<div dir="auto"><br>
</div>
</div>
<br>
<span style="font-family:monospace; font-size:10.4px; white-space:pre-wrap">-- **************************************************** Giuliana Materzanini Theory and Simulation of Materials École Polytechnique Fédérale de Lausanne ****************************************************</span><br>
<div dir="auto"><br>
</div>
<div><br>
<div class="x_elided-text">On Jan 18, 2019 09:01, LEUNG Clarence <liangxy123@hotmail.com> wrote:<br type="attribution">
<blockquote style="margin:0 0 0 0.8ex; border-left:1px #ccc solid; padding-left:1ex">
<div dir="ltr">
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important">Dear Riccardo Bertossa,</span><br>
</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><br>
</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important">Can CPMD run in NVT? Now I perform a system at 300K. </span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><img style="max-width:100%" data-outlook-trace="F:0|T:1" src="cid:699ebdcb-eca4-4293-bb11-3ec1fa1e40db"><br>
</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><br>
</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important">Ekinc is go up all the time:</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><img style="max-width:100%" data-outlook-trace="F:0|T:1" src="cid:8e608b01-ff5b-495c-854f-8a5da861e9c3"><br>
</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important">ETOT and Econs go up all the time:</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><img style="max-width:100%" data-outlook-trace="F:0|T:1" src="cid:4cc11732-f5e7-4524-965a-575db70e4f00"><br>
</span></div>
<div><font color="#212121"><span style="font-size:15px">Econt is not a constant:</span></font></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><img style="max-width:100%" data-outlook-trace="F:0|T:1" src="cid:f77d6356-1df6-473c-a91a-0c0da4b153a0"><br>
</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><br>
</span></div>
<div><font color="#212121"><span style="font-size:15px">I have run 0K simulation to go to the ground state and give 300K, the input file is </span></font></div>
<div><font color="#212121"><span style="font-size:15px"><br>
<div><br>
<div>&CONTROL<br>
</div>
<div> calculation='cp' ,</div>
<div> etot_conv_thr = 3.5D-6 ,<br>
</div>
<div> forc_conv_thr = 4.0D-4 ,<br>
</div>
<div> ekin_conv_thr = 1d-4 ,<br>
</div>
<div> pseudo_dir='/home/qeuser/SSSP_acc_PBE' ,<br>
</div>
<div> nstep = 70000 ,<br>
</div>
<div> tstress = .false. ,<br>
</div>
<div> tprnfor = .false. ,<br>
</div>
<div> dt=2.067,<br>
</div>
<div> isave = 100,<br>
</div>
<div> iprint = 10,<br>
</div>
<div> ndr = 56,<br>
</div>
<div> ndw = 57,<br>
</div>
<div> restart_mode = 'restart',<br>
</div>
<div> verbosity = 'low' ,<br>
</div>
<div>/<br>
</div>
<div><br>
</div>
<div>&SYSTEM<br>
</div>
<div> ibrav=14,<br>
</div>
<div> celldm(1)=36.1187133640d0, celldm(2)=0.6119121863d0, celldm(3)=1.3079965678d0,<br>
</div>
<div> celldm(4)=0.0000000000d0, celldm(5)=0.0000000000d0, celldm(6)=0.0000000000d0,<br>
</div>
<div> nat=63,<br>
</div>
<div> ntyp=2,<br>
</div>
<div> ecutwfc=50,<br>
</div>
<div> ecutrho=400,<br>
</div>
<div> input_dft='PBE',<br>
</div>
<div> vdw_corr = 'DFT-D3' ,<br>
</div>
<div> nr1b = 16 ,<br>
</div>
<div> nr2b = 16,<br>
</div>
<div> nr3b = 16 ,<br>
</div>
<div> nosym = .true. ,<br>
</div>
<div>/<br>
</div>
<div>&ELECTRONS<br>
</div>
<div> emass = 400<br>
</div>
<div> emass_cutoff = 2.50,<br>
</div>
<div> electron_dynamics = 'verlet' ,<br>
</div>
<div>/<br>
</div>
<div>&IONS<br>
</div>
<div> ion_dynamics = 'verlet',<br>
</div>
<div> tempw = 300 ,<br>
</div>
<div> ion_temperature = 'nose' ,<br>
</div>
<div> fnosep=6.6666,<br>
</div>
<div> ion_radius(1)=1.0,<br>
</div>
<div> ion_radius(2)=1.0,<br>
</div>
<div>/<br>
</div>
<div><br>
</div>
<div>ATOMIC_SPECIES<br>
</div>
<div> C 12.010700d0 C_pbe_v1.2.uspp.F.UPF<br>
</div>
<div> P 30.973800d0 P.pbe-n-rrkjus_psl.1.0.0.UPF<br>
</div>
<div><br>
</div>
<div>ATOMIC_POSITIONS {crystal}<br>
</div>
<div>P 0.207062953 0.994563394 0.532135751<br>
</div>
<div>P 0.042823633 0.994796583 0.465770116<br>
</div>
<div>C 0.157559602 0.119473623 0.509211511<br>
</div>
<div>C 0.092142096 0.120398444 0.486938482<br>
</div>
<div>P 0.453113260 0.016237452 0.533698293<br>
</div>
<div>P 0.289980002 0.986689982 0.464529400<br>
</div>
<div>C 0.399646081 0.133053286 0.505994952<br>
</div>
<div>C 0.335858066 0.117232823 0.482213070<br>
</div>
<div>P 0.704320783 0.007706925 0.532982064<br>
</div>
<div>P 0.538824580 0.008408401 0.468045855<br>
</div>
<div>C 0.654037234 0.132822314 0.511474768<br>
</div>
<div>C 0.587848371 0.135094109 0.489114957<br>
</div>
<div>P 0.956731588 -0.000006745 0.532145072<br>
</div>
<div>P 0.791554157 0.002228032 0.466394516<br>
</div>
<div>C 0.907495292 0.125510515 0.509696521<br>
</div>
<div>C 0.841931621 0.126642797 0.487430517<br>
</div>
<div>P 0.208266817 0.243782922 0.529541853<br>
</div>
<div>P 0.043965854 0.246589308 0.464392818<br>
</div>
<div>C 0.158728245 0.369838186 0.509463992<br>
</div>
<div>C 0.093217169 0.370873210 0.486709312<br>
</div>
<div>P 0.424177849 0.286343852 0.516852430<br>
</div>
<div>P 0.290089532 0.244400471 0.459582516<br>
</div>
<div>C 0.349540011 0.348792825 0.487513040<br>
</div>
<div>P 0.705574516 0.255089554 0.532107492<br>
</div>
<div>P 0.542012221 0.260506971 0.464249905<br>
</div>
<div>C 0.656129286 0.380833823 0.512136142<br>
</div>
<div>C 0.590214180 0.381152001 0.490082742<br>
</div>
<div>P 0.957108151 0.250073183 0.531244245<br>
</div>
<div>P 0.792998637 0.251922321 0.464998669<br>
</div>
<div>C 0.907321789 0.375462368 0.510050868<br>
</div>
<div>C 0.841746979 0.376334296 0.487596817<br>
</div>
<div>P 0.208402877 0.492352243 0.532960869<br>
</div>
<div>P 0.043963546 0.496372026 0.465432581<br>
</div>
<div>C 0.160144417 0.618157610 0.509696507<br>
</div>
<div>C 0.094342113 0.619600026 0.487659242<br>
</div>
<div>P 0.471073678 0.513328655 0.548894023<br>
</div>
<div>P 0.309129724 0.486227608 0.474070256<br>
</div>
<div>C 0.414925399 0.629235003 0.523346545<br>
</div>
<div>C 0.350961159 0.616373438 0.499640968<br>
</div>
<div>P 0.705395802 0.505478539 0.534378721<br>
</div>
<div>P 0.537192856 0.506995560 0.474222102<br>
</div>
<div>C 0.656825419 0.631333460 0.511436510<br>
</div>
<div>C 0.590845794 0.632466501 0.490389008<br>
</div>
<div>P 0.956482750 0.499986748 0.532254831<br>
</div>
<div>P 0.791270143 0.501641183 0.466922839<br>
</div>
<div>C 0.906923580 0.625196225 0.510129362<br>
</div>
<div>C 0.841214140 0.626345388 0.488309739<br>
</div>
<div>P 0.207667541 0.743674910 0.533472131<br>
</div>
<div>P 0.043998636 0.744658734 0.465730512<br>
</div>
<div>C 0.158052412 0.868776604 0.510578825<br>
</div>
<div>C 0.092761413 0.869723388 0.488195850<br>
</div>
<div>P 0.461194613 0.761061943 0.539728957<br>
</div>
<div>P 0.299530254 0.737206731 0.471960596<br>
</div>
<div>C 0.407654987 0.881987587 0.515312903<br>
</div>
<div>C 0.343486860 0.870097791 0.492007540<br>
</div>
<div>P 0.706175574 0.757137135 0.532107627<br>
</div>
<div>P 0.539960743 0.756974729 0.469099032<br>
</div>
<div>C 0.655720285 0.882343139 0.510585276<br>
</div>
<div>C 0.589586421 0.883272199 0.489712695<br>
</div>
<div>P 0.956945276 0.749651294 0.531828394<br>
</div>
<div>P 0.791991567 0.752132650 0.465926241<br>
</div>
<div>C 0.907222485 0.875386768 0.509910655<br>
</div>
<div>C 0.841486983 0.876756958 0.488249976<br>
</div>
<div><br>
</div>
<div>K_POINTS {gamma}<br>
</div>
<div><br>
</div>
<div>Thanks very much.</div>
<div><br>
</div>
<div>LIANG Xiongyi</div>
</div>
</span></font></div>
<div></div>
<hr style="display:inline-block; width:98%">
<div dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>发件人:</b> users <users-bounces@lists.quantum-espresso.org> 代表 Riccardo Bertossa <rbertoss@sissa.it><br>
<b>发送时间:</b> 2019年1月18日 2:24<br>
<b>收件人:</b> users@lists.quantum-espresso.org<br>
<b>主题:</b> Re: [QE-users] Question on CPMD</font>
<div> </div>
</div>
<div style="background-color:#ffffff">
<p>dear LIANG,</p>
<p><br>
</p>
<p>when you run in the NVE you should have something like this:<br>
</p>
<p><img alt="" data-outlook-trace="F:0|T:1" src="cid:part1.2BBB1DF7.418C4223@sissa.it"></p>
<p><img alt="" data-outlook-trace="F:0|T:1" src="cid:part2.309ED1CB.07CFEBCF@sissa.it"></p>
<p>if I am not wrong:<br>
</p>
<p>ekinc is the kinetic energy of the electrons<br>
</p>
<p>etot is the total potential energy (calculated with DFT)<br>
</p>
<p>econs is the energy that to make a good simulation you want to make as constant as possible, but it will oscillate because electrons have a mass and a kinetic energy, so it will never be constant.<br>
</p>
<p>econt is the constant of motion of the CP lagrangian, and this must always remain approximately constant, within the integration error of the verlet algorithm. If it is not constant your simulation is not good and you have to change some parameters.<br>
</p>
<p><br>
</p>
<p><br>
</p>
<p>best regards,</p>
<p>Riccardo Bertossa</p>
<p>SISSA<br>
</p>
<p><br>
</p>
<div>On 17/01/19 15:54, LEUNG Clarence wrote:<br>
</div>
<blockquote>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
Dear QE users,</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<br>
</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
From CPMD, we can get EKINC ETOT ENTHAL ECONS and ECONT of the system. Which one is the total energy of the system?</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
ETOT? or Ekinc + Etot ? or Etot - Ekinc ?</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<br>
</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
Thanks.</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<br>
</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
LIANG Xiongyi</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
City University of Hong Kong</div>
<br>
<fieldset></fieldset>
<pre>_______________________________________________
users mailing list
<a href="mailto:users@lists.quantum-espresso.org">users@lists.quantum-espresso.org</a>
<a href="https://lists.quantum-espresso.org/mailman/listinfo/users">https://lists.quantum-espresso.org/mailman/listinfo/users</a></pre>
</blockquote>
</div>
</div>
</blockquote>
</div>
<br>
</div>
</div>
<br>
<div><br>
<div class="x_elided-text">On Jan 18, 2019 09:01, LEUNG Clarence <liangxy123@hotmail.com> wrote:<br type="attribution">
<blockquote style="margin:0 0 0 0.8ex; border-left:1px #ccc solid; padding-left:1ex">
<div dir="ltr">
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important">Dear Riccardo Bertossa,</span><br>
</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><br>
</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important">Can CPMD run in NVT? Now I perform a system at 300K. </span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><img style="max-width:100%" data-outlook-trace="F:0|T:1" src="cid:699ebdcb-eca4-4293-bb11-3ec1fa1e40db"><br>
</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><br>
</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important">Ekinc is go up all the time:</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><img style="max-width:100%" data-outlook-trace="F:0|T:1" src="cid:8e608b01-ff5b-495c-854f-8a5da861e9c3"><br>
</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important">ETOT and Econs go up all the time:</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><img style="max-width:100%" data-outlook-trace="F:0|T:1" src="cid:4cc11732-f5e7-4524-965a-575db70e4f00"><br>
</span></div>
<div><font color="#212121"><span style="font-size:15px">Econt is not a constant:</span></font></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><img style="max-width:100%" data-outlook-trace="F:0|T:1" src="cid:f77d6356-1df6-473c-a91a-0c0da4b153a0"><br>
</span></div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<span style="color:rgb(33 ,33 ,33); font-size:15px; background-color:rgb(255 ,255 ,255); display:inline!important"><br>
</span></div>
<div><font color="#212121"><span style="font-size:15px">I have run 0K simulation to go to the ground state and give 300K, the input file is </span></font></div>
<div><font color="#212121"><span style="font-size:15px"><br>
<div><br>
<div>&CONTROL<br>
</div>
<div> calculation='cp' ,</div>
<div> etot_conv_thr = 3.5D-6 ,<br>
</div>
<div> forc_conv_thr = 4.0D-4 ,<br>
</div>
<div> ekin_conv_thr = 1d-4 ,<br>
</div>
<div> pseudo_dir='/home/qeuser/SSSP_acc_PBE' ,<br>
</div>
<div> nstep = 70000 ,<br>
</div>
<div> tstress = .false. ,<br>
</div>
<div> tprnfor = .false. ,<br>
</div>
<div> dt=2.067,<br>
</div>
<div> isave = 100,<br>
</div>
<div> iprint = 10,<br>
</div>
<div> ndr = 56,<br>
</div>
<div> ndw = 57,<br>
</div>
<div> restart_mode = 'restart',<br>
</div>
<div> verbosity = 'low' ,<br>
</div>
<div>/<br>
</div>
<div><br>
</div>
<div>&SYSTEM<br>
</div>
<div> ibrav=14,<br>
</div>
<div> celldm(1)=36.1187133640d0, celldm(2)=0.6119121863d0, celldm(3)=1.3079965678d0,<br>
</div>
<div> celldm(4)=0.0000000000d0, celldm(5)=0.0000000000d0, celldm(6)=0.0000000000d0,<br>
</div>
<div> nat=63,<br>
</div>
<div> ntyp=2,<br>
</div>
<div> ecutwfc=50,<br>
</div>
<div> ecutrho=400,<br>
</div>
<div> input_dft='PBE',<br>
</div>
<div> vdw_corr = 'DFT-D3' ,<br>
</div>
<div> nr1b = 16 ,<br>
</div>
<div> nr2b = 16,<br>
</div>
<div> nr3b = 16 ,<br>
</div>
<div> nosym = .true. ,<br>
</div>
<div>/<br>
</div>
<div>&ELECTRONS<br>
</div>
<div> emass = 400<br>
</div>
<div> emass_cutoff = 2.50,<br>
</div>
<div> electron_dynamics = 'verlet' ,<br>
</div>
<div>/<br>
</div>
<div>&IONS<br>
</div>
<div> ion_dynamics = 'verlet',<br>
</div>
<div> tempw = 300 ,<br>
</div>
<div> ion_temperature = 'nose' ,<br>
</div>
<div> fnosep=6.6666,<br>
</div>
<div> ion_radius(1)=1.0,<br>
</div>
<div> ion_radius(2)=1.0,<br>
</div>
<div>/<br>
</div>
<div><br>
</div>
<div>ATOMIC_SPECIES<br>
</div>
<div> C 12.010700d0 C_pbe_v1.2.uspp.F.UPF<br>
</div>
<div> P 30.973800d0 P.pbe-n-rrkjus_psl.1.0.0.UPF<br>
</div>
<div><br>
</div>
<div>ATOMIC_POSITIONS {crystal}<br>
</div>
<div>P 0.207062953 0.994563394 0.532135751<br>
</div>
<div>P 0.042823633 0.994796583 0.465770116<br>
</div>
<div>C 0.157559602 0.119473623 0.509211511<br>
</div>
<div>C 0.092142096 0.120398444 0.486938482<br>
</div>
<div>P 0.453113260 0.016237452 0.533698293<br>
</div>
<div>P 0.289980002 0.986689982 0.464529400<br>
</div>
<div>C 0.399646081 0.133053286 0.505994952<br>
</div>
<div>C 0.335858066 0.117232823 0.482213070<br>
</div>
<div>P 0.704320783 0.007706925 0.532982064<br>
</div>
<div>P 0.538824580 0.008408401 0.468045855<br>
</div>
<div>C 0.654037234 0.132822314 0.511474768<br>
</div>
<div>C 0.587848371 0.135094109 0.489114957<br>
</div>
<div>P 0.956731588 -0.000006745 0.532145072<br>
</div>
<div>P 0.791554157 0.002228032 0.466394516<br>
</div>
<div>C 0.907495292 0.125510515 0.509696521<br>
</div>
<div>C 0.841931621 0.126642797 0.487430517<br>
</div>
<div>P 0.208266817 0.243782922 0.529541853<br>
</div>
<div>P 0.043965854 0.246589308 0.464392818<br>
</div>
<div>C 0.158728245 0.369838186 0.509463992<br>
</div>
<div>C 0.093217169 0.370873210 0.486709312<br>
</div>
<div>P 0.424177849 0.286343852 0.516852430<br>
</div>
<div>P 0.290089532 0.244400471 0.459582516<br>
</div>
<div>C 0.349540011 0.348792825 0.487513040<br>
</div>
<div>P 0.705574516 0.255089554 0.532107492<br>
</div>
<div>P 0.542012221 0.260506971 0.464249905<br>
</div>
<div>C 0.656129286 0.380833823 0.512136142<br>
</div>
<div>C 0.590214180 0.381152001 0.490082742<br>
</div>
<div>P 0.957108151 0.250073183 0.531244245<br>
</div>
<div>P 0.792998637 0.251922321 0.464998669<br>
</div>
<div>C 0.907321789 0.375462368 0.510050868<br>
</div>
<div>C 0.841746979 0.376334296 0.487596817<br>
</div>
<div>P 0.208402877 0.492352243 0.532960869<br>
</div>
<div>P 0.043963546 0.496372026 0.465432581<br>
</div>
<div>C 0.160144417 0.618157610 0.509696507<br>
</div>
<div>C 0.094342113 0.619600026 0.487659242<br>
</div>
<div>P 0.471073678 0.513328655 0.548894023<br>
</div>
<div>P 0.309129724 0.486227608 0.474070256<br>
</div>
<div>C 0.414925399 0.629235003 0.523346545<br>
</div>
<div>C 0.350961159 0.616373438 0.499640968<br>
</div>
<div>P 0.705395802 0.505478539 0.534378721<br>
</div>
<div>P 0.537192856 0.506995560 0.474222102<br>
</div>
<div>C 0.656825419 0.631333460 0.511436510<br>
</div>
<div>C 0.590845794 0.632466501 0.490389008<br>
</div>
<div>P 0.956482750 0.499986748 0.532254831<br>
</div>
<div>P 0.791270143 0.501641183 0.466922839<br>
</div>
<div>C 0.906923580 0.625196225 0.510129362<br>
</div>
<div>C 0.841214140 0.626345388 0.488309739<br>
</div>
<div>P 0.207667541 0.743674910 0.533472131<br>
</div>
<div>P 0.043998636 0.744658734 0.465730512<br>
</div>
<div>C 0.158052412 0.868776604 0.510578825<br>
</div>
<div>C 0.092761413 0.869723388 0.488195850<br>
</div>
<div>P 0.461194613 0.761061943 0.539728957<br>
</div>
<div>P 0.299530254 0.737206731 0.471960596<br>
</div>
<div>C 0.407654987 0.881987587 0.515312903<br>
</div>
<div>C 0.343486860 0.870097791 0.492007540<br>
</div>
<div>P 0.706175574 0.757137135 0.532107627<br>
</div>
<div>P 0.539960743 0.756974729 0.469099032<br>
</div>
<div>C 0.655720285 0.882343139 0.510585276<br>
</div>
<div>C 0.589586421 0.883272199 0.489712695<br>
</div>
<div>P 0.956945276 0.749651294 0.531828394<br>
</div>
<div>P 0.791991567 0.752132650 0.465926241<br>
</div>
<div>C 0.907222485 0.875386768 0.509910655<br>
</div>
<div>C 0.841486983 0.876756958 0.488249976<br>
</div>
<div><br>
</div>
<div>K_POINTS {gamma}<br>
</div>
<div><br>
</div>
<div>Thanks very much.</div>
<div><br>
</div>
<div>LIANG Xiongyi</div>
</div>
</span></font></div>
<div></div>
<hr style="display:inline-block; width:98%">
<div dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>发件人:</b> users <users-bounces@lists.quantum-espresso.org> 代表 Riccardo Bertossa <rbertoss@sissa.it><br>
<b>发送时间:</b> 2019年1月18日 2:24<br>
<b>收件人:</b> users@lists.quantum-espresso.org<br>
<b>主题:</b> Re: [QE-users] Question on CPMD</font>
<div> </div>
</div>
<div style="background-color:#ffffff">
<p>dear LIANG,</p>
<p><br>
</p>
<p>when you run in the NVE you should have something like this:<br>
</p>
<p><img alt="" data-outlook-trace="F:0|T:1" src="cid:part1.2BBB1DF7.418C4223@sissa.it"></p>
<p><img alt="" data-outlook-trace="F:0|T:1" src="cid:part2.309ED1CB.07CFEBCF@sissa.it"></p>
<p>if I am not wrong:<br>
</p>
<p>ekinc is the kinetic energy of the electrons<br>
</p>
<p>etot is the total potential energy (calculated with DFT)<br>
</p>
<p>econs is the energy that to make a good simulation you want to make as constant as possible, but it will oscillate because electrons have a mass and a kinetic energy, so it will never be constant.<br>
</p>
<p>econt is the constant of motion of the CP lagrangian, and this must always remain approximately constant, within the integration error of the verlet algorithm. If it is not constant your simulation is not good and you have to change some parameters.<br>
</p>
<p><br>
</p>
<p><br>
</p>
<p>best regards,</p>
<p>Riccardo Bertossa</p>
<p>SISSA<br>
</p>
<p><br>
</p>
<div>On 17/01/19 15:54, LEUNG Clarence wrote:<br>
</div>
<blockquote>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
Dear QE users,</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<br>
</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
From CPMD, we can get EKINC ETOT ENTHAL ECONS and ECONT of the system. Which one is the total energy of the system?</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
ETOT? or Ekinc + Etot ? or Etot - Ekinc ?</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<br>
</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
Thanks.</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
<br>
</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
LIANG Xiongyi</div>
<div style="font-family:'calibri' ,'helvetica' ,sans-serif; font-size:12pt; color:rgb(0 ,0 ,0)">
City University of Hong Kong</div>
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