[CPMD-list] temperature Drift in CPMD
Samir H. Mushrif
samir.mushrif at mail.mcgill.ca
Wed Oct 3 19:21:27 CET 2007
Hello CPMD Users,
First of all I would like to thank Axel for his
valuable suggestions in the past about possible solutions to overcome
the problem I had with QUENCH BO ELECTRONS and about installing CPMD in
parallel.
(http://www.cpmd.org/pipermail/cpmd-list/2007-July/003994.html and
http://www.cpmd.org/pipermail/cpmd-list/2007-July/004001.html)
As per Axel's suggestions, I have successfully installed CPMD in parallel.
I have a system with 210 atoms (C, H, O and Pd, 596 electrons) at 500 K
and I equilibrated the system using TEMPCONTROL IONS option in CPMD.
After ~1000 MD steps (a cycle of a couple of hundred MD steps followed
by wavefunction optimization and QUENCH ELECTRONS, preserving the ionic
velocities using GEOMETRY file) I observed that the EKS is not drifting
and is oscillating around a mean value. The EKINC was observed to be
approximately 0.14. I used this value of EKINC and shifted to NOSE IONS
MASSIVE. But now when I run my simulation, I observed that the TEMP
keeps decreasing and it goes upto 300 K in the first 70 MD steps. Am I
doing something wrong here or shall I wait for some more time (probably
a few hundred MD steps) to see the trend since it is too early to
conclude that something is going wrong here.
My input file looks as follows:
&CPMD
MOLECULAR DYNAMICS CP
RESTART WAVEFUNCTION COORDINATES CELL GEOFILE
TEMPERATURE
500.0
NOSE IONS MASSIVE
500.0 1800.0 ************
Since I have a system with polyaromatic hydrocarbons, I took the
frequency of a C-C bond vibration as the characteristic frequency for
NOSE IONS
************
NOSE ELECTRONS
0.14 10000.0
LSD
MAXSTEP
1000
TRAJECTORY XYZ SAMPLE FORCES
5
TIMESTEP
4.0
EMASS
600.0
FILEPATH
/home/grad/samir/prod1/
MEMORY BIG
&END
.
.
.
.
Relevant part of my output file is as follows:
NFI EKINC TEMPP EKS ECLASSIC EHAM
DIS TCPU
1 0.00034 490.7 -861.96227 -859.89980 -859.89946
0.210E-04 940.27
2 0.00434 470.2 -861.94521 -859.90271 -859.89837
0.827E-04 954.48
3 0.01558 443.0 -861.92918 -859.91403 -859.89845
0.182E-03 945.44
4 0.03282 414.1 -861.91762 -859.93137 -859.89854
0.314E-03 930.96
5 0.05239 387.2 -861.91034 -859.95102 -859.89862
0.476E-03 974.99
6 0.07124 364.1 -861.90615 -859.96993 -859.89870
0.664E-03 936.85
7 0.08761 345.5 -861.90387 -859.98635 -859.89873
0.875E-03 940.03
8 0.10087 331.2 -861.90274 -859.99964 -859.89877
0.111E-02 939.76
9 0.11075 320.8 -861.90204 -860.00955 -859.89881
0.136E-02 933.02
10 0.11724 313.6 -861.90113 -860.01607 -859.89882
0.162E-02 943.45
11 0.12060 309.0 -861.89964 -860.01943 -859.89883
0.191E-02 944.31
12 0.12125 306.4 -861.89737 -860.02006 -859.89881
0.221E-02 968.37
13 0.11983 305.3 -861.89451 -860.01862 -859.89879
0.253E-02 957.94
14 0.11702 305.3 -861.89137 -860.01578 -859.89876
0.287E-02 935.75
15 0.11344 306.3 -861.88831 -860.01217 -859.89873
0.323E-02 929.10
16 0.10963 307.8 -861.88561 -860.00835 -859.89872
0.361E-02 960.17
17 0.10596 309.7 -861.88341 -860.00467 -859.89871
0.401E-02 938.94
18 0.10269 311.7 -861.88174 -860.00140 -859.89871
0.443E-02 945.02
19 0.09991 313.7 -861.88054 -859.99863 -859.89872
0.487E-02 950.65
20 0.09763 315.6 -861.87965 -859.99636 -859.89872
0.533E-02 955.43
21 0.09584 317.1 -861.87894 -859.99457 -859.89873
0.581E-02 935.81
22 0.09447 318.3 -861.87828 -859.99319 -859.89873
0.632E-02 935.46
23 0.09345 319.1 -861.87757 -859.99217 -859.89872
0.684E-02 929.06
24 0.09270 319.5 -861.87676 -859.99142 -859.89872
0.739E-02 954.78
25 0.09216 319.7 -861.87586 -859.99087 -859.89871
0.795E-02 937.35
26 0.09178 319.6 -861.87490 -859.99048 -859.89870
0.854E-02 941.61
27 0.09153 319.5 -861.87396 -859.99022 -859.89869
0.915E-02 974.73
28 0.09140 319.3 -861.87313 -859.99008 -859.89868
0.977E-02 938.41
29 0.09140 319.2 -861.87253 -859.99007 -859.89867
0.104E-01 942.28
30 0.09152 319.3 -861.87222 -859.99018 -859.89866
0.111E-01 943.61
31 0.09176 319.7 -861.87227 -859.99041 -859.89866
0.118E-01 938.72
32 0.09208 320.3 -861.87268 -859.99074 -859.89865
0.125E-01 935.33
33 0.09246 321.3 -861.87344 -859.99111 -859.89865
0.132E-01 952.80
34 0.09284 322.5 -861.87449 -859.99149 -859.89865
0.139E-01 945.53
35 0.09315 324.0 -861.87575 -859.99180 -859.89865
0.147E-01 940.43
36 0.09336 325.8 -861.87715 -859.99201 -859.89865
0.154E-01 955.35
37 0.09343 327.8 -861.87862 -859.99208 -859.89865
0.162E-01 945.36
38 0.09337 329.9 -861.88012 -859.99202 -859.89865
0.170E-01 947.16
39 0.09322 332.2 -861.88163 -859.99187 -859.89864
0.179E-01 942.03
40 0.09303 334.5 -861.88315 -859.99167 -859.89864
0.187E-01 957.14
41 0.09287 336.8 -861.88469 -859.99151 -859.89863
0.196E-01 968.58
42 0.09279 339.0 -861.88625 -859.99142 -859.89863
0.205E-01 969.97
43 0.09284 341.2 -861.88784 -859.99147 -859.89863
0.214E-01 949.84
44 0.09304 343.1 -861.88943 -859.99167 -859.89863
0.224E-01 979.63
45 0.09340 344.9 -861.89098 -859.99202 -859.89863
0.233E-01 956.39
46 0.09389 346.4 -861.89245 -859.99252 -859.89862
0.243E-01 926.91
47 0.09449 347.7 -861.89379 -859.99312 -859.89862
0.253E-01 945.46
48 0.09516 348.7 -861.89494 -859.99378 -859.89862
0.264E-01 952.41
49 0.09586 349.5 -861.89587 -859.99448 -859.89862
0.274E-01 969.87
50 0.09653 350.0 -861.89654 -859.99515 -859.89862
0.285E-01 944.25
51 0.09716 350.2 -861.89691 -859.99578 -859.89862
0.296E-01 956.94
52 0.09771 350.2 -861.89697 -859.99632 -859.89861
0.307E-01 950.04
53 0.09815 349.9 -861.89670 -859.99676 -859.89861
0.318E-01 952.96
54 0.09847 349.5 -861.89611 -859.99708 -859.89861
0.330E-01 970.18
55 0.09867 348.8 -861.89518 -859.99727 -859.89860
0.341E-01 928.44
56 0.09873 347.9 -861.89393 -859.99733 -859.89860
0.353E-01 940.75
57 0.09866 346.8 -861.89235 -859.99726 -859.89860
0.365E-01 950.19
58 0.09846 345.5 -861.89042 -859.99705 -859.89859
0.377E-01 981.22
59 0.09813 344.0 -861.88816 -859.99672 -859.89859
0.390E-01 955.57
60 0.09768 342.3 -861.88555 -859.99627 -859.89859
0.402E-01 956.94
61 0.09713 340.2 -861.88259 -859.99571 -859.89859
0.415E-01 943.63
62 0.09648 338.0 -861.87928 -859.99506 -859.89858
0.428E-01 945.27
63 0.09574 335.5 -861.87563 -859.99432 -859.89858
0.440E-01 977.58
64 0.09495 332.7 -861.87166 -859.99353 -859.89857
0.453E-01 931.39
65 0.09413 329.6 -861.86739 -859.99270 -859.89857
0.466E-01 972.12
66 0.09331 326.3 -861.86286 -859.99187 -859.89856
0.479E-01 948.16
67 0.09249 322.8 -861.85810 -859.99105 -859.89856
0.493E-01 938.37
68 0.09170 319.0 -861.85316 -859.99026 -859.89855
0.506E-01 938.60
Thanks and Regards
Samir
_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/
Samir H. Mushrif
Department of Chemical Engineering
McGill University
3610 University Street
Montreal, Quebec H3A2B2
Canada
Ph: (Lab)514-398-5170
(Off)514-398-4169
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