[gmx-users] the target temperature

David spoel at xray.bmc.uu.se
Tue Apr 6 22:33:01 CEST 2004


On Tue, 2004-04-06 at 22:21, Qi Sun wrote:
> Hi all the Gromacs users:
>    I am a beginning of Gromacs and did some research on YASP before. My 
> system is about pure Cyclohexane right now. total 674 molecules. There 
> are two problems:
> 1. gen_vel is set to yes, and gen_temp is set to 325K. after I start 
> even 1 number of step at dt (0.00000002). The temperature still starts 
> from 4000~8000K high. I don't know what is going on.
> 2. Attached is my topology file, can somebody have a look and see if the 
> topology file is wrong.

topology looks OK. How about the coordinates?
> 
> Thank you  so much.
> 
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> Qi Sun
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> ______________________________________________________________________
> ;Topology for 674 Cyclohexane 
> ;The force field files to be included
> #include "ffgmx.itp"
> 
> [atomtypes]
>   MEC    12.0     0.000     A      0.148927E-02    0.1854459E-05
>   MEH    1.007825 0.000     A      0.222967E-03    0.6575946E-07
> 
> [constrainttypes]
>   MEC  MEC    1    0.15
>   MEC  MEH    1    0.10
> 
> [angletypes]
> ;  i      j     k    func   th0      cth
>    MEC   MEC   MEC     1    109.5    335
>    MEC   MEC   MEH     1    109.5    420
>    MEH   MEC   MEH     1    109.5    290
> 
> [dihedraltypes]
> ;  j     k      func   phi0     cp    mult
>    MEC   MEC     1     180.0    10     3
> ;This is Cyclohexane
> [moleculetype]
> Cyclohexane 3
> 
> [atoms]
> ;  nr    type    resnr    residu         atom   cgnr    charge
>     1     MEC       1      Cyclohexane   C1       1       0
>     2     MEC       1      Cyclohexane   C2       1       0
>     3     MEC       1      Cyclohexane   C3       1       0
>     4     MEC       1      Cyclohexane   C4       1       0
>     5     MEC       1      Cyclohexane   C5       1       0
>     6     MEC       1      Cyclohexane   C6       1       0
>     7     MEH       1      Cyclohexane   H7       2       0
>     8     MEH       1      Cyclohexane   H8       2       0
>     9     MEH       1      Cyclohexane   H9       2       0
>    10     MEH       1      Cyclohexane   H10      2       0
>    11     MEH       1      Cyclohexane   H11      2       0
>    12     MEH       1      Cyclohexane   H12      2       0
>    13     MEH       1      Cyclohexane   H13      2       0
>    14     MEH       1      Cyclohexane   H14      2       0
>    15     MEH       1      Cyclohexane   H15      2       0
>    16     MEH       1      Cyclohexane   H16      2       0
>    17     MEH       1      Cyclohexane   H17      2       0 
>    18     MEH       1      Cyclohexane   H18      2       0  
> 
> [constraints]
> ;   ai  aj  function   constraint distance
>     1   2    1             
>     2   3    1              
>     4   3    1            
>     5   4    1               
>     5   6    1            
>     1   6    1               
>     1   7    1               
>     1   8    1             
>     2   9    1               
>     2   10   1               
>     3   11   1               
>     3   12   1               
>     4   13   1               
>     4   14   1               
>     5   15   1               
>     5   16   1               
>     6   17   1               
>     6   18   1               
> 
> [pairs]
> ;  ai   aj   funct    c6     c12
>    1    4     1       0.0    0.0
>    1    11    1       0.0    0.0
>    1    12    1       0.0    0.0
>    1    15    1       0.0    0.0
>    1    16    1       0.0    0.0
>    2    5     1       0.0    0.0
>    2    13    1       0.0    0.0
>    2    14    1       0.0    0.0
>    2    17    1       0.0    0.0
>    2    18    1       0.0    0.0
>    3    6     1       0.0    0.0
>    3    7     1       0.0    0.0
>    3    8     1       0.0    0.0
>    3    15    1       0.0    0.0
>    3    16    1       0.0    0.0
>    4    9     1       0.0    0.0
>    4    10    1       0.0    0.0
>    4    17    1       0.0    0.0
>    4    18    1       0.0    0.0
>    5    7     1       0.0    0.0
>    5    8     1       0.0    0.0
>    5    11    1       0.0    0.0
>    5    12    1       0.0    0.0 
>    6    9     1       0.0    0.0
>    6    10    1       0.0    0.0
>    6    13    1       0.0    0.0
>    6    14    1       0.0    0.0
>    7    9     1       0.0    0.0
>    7    10    1       0.0    0.0
>    7    17    1       0.0    0.0
>    7    18    1       0.0    0.0
>    8    9     1       0.0    0.0
>    8    10    1       0.0    0.0
>    8    17    1       0.0    0.0
>    8    18    1       0.0    0.0
>    9    11    1       0.0    0.0
>    9    12    1       0.0    0.0
>    10   11    1       0.0    0.0
>    10   12    1       0.0    0.0
>    11   13    1       0.0    0.0
>    11   14    1       0.0    0.0
>    12   13    1       0.0    0.0
>    12   14    1       0.0    0.0
>    13   15    1       0.0    0.0
>    13   16    1       0.0    0.0
>    14   15    1       0.0    0.0
>    14   16    1       0.0    0.0
>    15   17    1       0.0    0.0
>    15   18    1       0.0    0.0
>    16   17    1       0.0    0.0
>    16   18    1       0.0    0.0
> 
> [angles]
> ;   ai   aj   ak   funct       c0   c1
>     1    2    3      1
>     1    2    9      1
>     1    2    10     1
>     2    3    4      1
>     2    3    11     1
>     2    3    12     1
>     9    2    3      1
>     10   2    3      1
>     9    2    10     1
>     3    4    5      1
>     3    4    13     1
>     3    4    14     1
>     11   3    4      1
>     12   3    4      1
>     11   3    12     1
>     4    5    6      1
>     4    5    15     1
>     4    5    16     1
>     13   4    5      1
>     14   4    5      1
>     13   4    14     1
>     5    6    1      1
>     5    6    17     1
>     5    6    18     1
>     15   5    6      1
>     16   5    6      1
>     15   5    16     1
>     6    1    2      1
>     6    1    7      1
>     6    1    8      1
>     17   6    1      1
>     18   6    1      1
>     17   6    18     1
>     7    1    2      1
>     8    1    2      1
>     7    1    8      1
>  [dihedrals]
> ;   ai   aj   funct
>      1    2    3    4       1
>      2    3    4    5       1
>      3    4    5    6       1
>      4    5    6    1       1
>      5    6    1    2       1
>      6    1    2    3       1
>  [system]
> ; Name
> Pure Cyclohexane
> [molecules]
> ; Compound    #mols
> Cyclohexane    674
-- 
David.
________________________________________________________________________
David van der Spoel, PhD, Assist. Prof., Molecular Biophysics group,
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596,  	75124 Uppsala, Sweden
phone:	46 18 471 4205		fax: 46 18 511 755
spoel at xray.bmc.uu.se	spoel at gromacs.org   http://xray.bmc.uu.se/~spoel
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