[gmx-users] topolbuild ( Failing to read oxygen in H2O )

大木啓輔 keisuke.ohki at keio.jp
Tue Nov 29 03:26:20 CET 2016


Dear Bruce D. Ray


Thank you for replying to my question.

I understood that I should not include water molecules in submit file to topolbuild
because water topology is given by spce.itp.

Then, should I give coordinates of water to *.gro file and delete parameters of water in topology file
when hydrate structure is the object of my study? 

Sincerely.


Keisuke Ohki
> 2016/11/29 3:45、Ray, Bruce D <bray at iupui.edu>のメール:
> 
> On Nov 26, 2016, at 4:19 AM, ???? <keisuke.ohki at keio.jp> wrote:
> 
>> Date: Sat, 26 Nov 2016 17:24:56 +0900
>> From: ???? <keisuke.ohki at keio.jp>
>> To: gromacs.org_gmx-users at maillist.sys.kth.se
>> Subject: [gmx-users]  topolbuild ( Failing to read oxygen in H2O )
>> Message-ID: <07C401C0-1755-433C-9E89-C7A9E8A87F0E at keio.jp>
>> Content-Type: text/plain; charset=us-ascii
>> 
>> Dear gromacs users
>> 
>> I have a question why topolbuild fails to read oxygen in H2O.
>> 
>> I want to make a topology file of methane hydrate structure with topolbuild and run simulation in gromacs.
>> 
>> I used following command line:
>> 
>> ./topolbuild -n ../HYDRATE_A -dir ../dat/gromacs -ff oplsaa -purge 0
>> 
>> .mol2 file that I  used then { 
>> 
>> @<TRIPOS>MOLECULE
>> ch4h2o_4.pdb
>> 46 36 10 0 0
>> SMALL
>> USER_CHARGES
>> 
>> 
>> @<TRIPOS>ATOM
>>     1 C           5.6060    1.6670    5.1720 C.3       1 LIG1   -0.4588
>>     2 H           6.2390    2.2990    5.8040 H         1 LIG1    0.1147
>>     3 H           4.9740    1.0350    5.8040 H         1 LIG1    0.1147
>>     4 H           4.9740    2.2990    4.5400 H         1 LIG1    0.1147
>>     5 H           6.2390    1.0350    4.5400 H         1 LIG1    0.1147
>>       :
>>    41 O           7.0060    1.7150    8.9340 O.3       9 H2O    -1.1794
>>    42 H           6.0130    1.7150    9.0510 H         9 H2O     0.5897
>>    43 H           7.4440    1.7150    9.8330 H         9 H2O     0.5897
>>    44 O           6.9570    1.7200    1.4090 O.3      10 H2O    -1.1794
>>    45 H           7.2050    0.8780    1.8880 H        10 H2O     0.5897
>>    46 H           7.2400    2.5080    1.9570 H        10 H2O     0.5897
>> @<TRIPOS>BOND
>>    1    1    2 1
>>    2    1    3 1
>>    3    1    4 1
>>    4    1    5 1
>>    :
>>   33   41   42 1
>>   34   41   43 1
>>   35   44   45 1
>>   36   44   46 1
>> @<TRIPOS>SUBSTRUCTURE
>>    1 LIG1     1 RESIDUE           4 A     LIG1     0 ROOT
>>    2 LIG1     6 RESIDUE           4 A     LIG1     0 ROOT
>>    3 LIG1    11 RESIDUE           4 A     LIG1     0 ROOT
>>    4 LIG1    16 RESIDUE           4 A     LIG1     0 ROOT
>>    5 LIG1    21 RESIDUE           4 A     LIG1     0 ROOT
>>    6 LIG1    26 RESIDUE           4 A     LIG1     0 ROOT
>>    7 LIG1    31 RESIDUE           4 A     LIG1     0 ROOT
>>    8 LIG1    36 RESIDUE           4 A     LIG1     0 ROOT
>>    9 H2O    41 RESIDUE           4 A     H2O     0 ROOT
>>   10 H2O    44 RESIDUE           4 A     H2O     0 ROOT
>> 
>> }
>> 
>> ( this file was used for trial, so this is not hydrate structure )
>> 
>> Then, I got this topology file {
>> 
>> ; The force field files to be included
>> #include "ffHYDRATE_A.itp"
>> 
>> [ moleculetype ]
>> ; name  nrexcl
>> ch4h2o_4.pdb   3
>> 
>> [ atoms ]
>> ;  nr    type   resnr   residu   atom   cgnr    charge      mass
>>   1    opls_138     1       LIG       C    1  -0.45880  12.01100       ;  -0.4588000
>>   2    opls_140     1       LIG       H    1   0.11470   1.00800       ;  -0.3441000
>>   3    opls_140     1       LIG       H    1   0.11470   1.00800       ;  -0.2294000
>>   4    opls_140     1       LIG       H    1   0.11470   1.00800       ;  -0.1147000
>>   5    opls_140     1       LIG       H    1   0.11470   1.00800       ;   0.0000000
>>   :
>>  41         O??     9       H2O       O    9  -1.17940  15.99940       ;  -1.1794000
>>  42    opls_435     9       H2O       H   10   0.58970   1.00800       ;  -0.5897000
>>  43    opls_435     9       H2O       H   11   0.58970   1.00800       ;   0.0000000
>>  44         O??    10       H2O       O   12  -1.17940  15.99940       ;  -1.1794000
>>  45    opls_435    10       H2O       H   13   0.58970   1.00800       ;  -0.5897000
>>  46    opls_435    10       H2O       H   14   0.58970   1.00800       ;   0.0000000
>> ; total molecule charge =   0.0000000
>> 
>> [ bonds ]
>> ;   ai  aj   funct      b0          kb
>>      1     2   1     0.10900      284512.       ;     C-     H
>>      1     3   1     0.10900      284512.       ;     C-     H
>>      1     4   1     0.10900      284512.       ;     C-     H
>>      1     5   1     0.10900      284512.       ;     C-     H
>>      :
>>     41    42                                    ;     O-     H
>>     41    43                                    ;     O-     H
>>     44    45                                    ;     O-     H
>>     44    46                                    ;     O-     H
>> 
>> [ pairs ]
>> 
>> [ angles ]
>> ; ai  aj  ak  funct      th0         cth
>>    3     1     2   1     107.800    276.1440     ;     H-     C-     H
>>    4     1     2   1     107.800    276.1440     ;     H-     C-     H
>>    5     1     2   1     107.800    276.1440     ;     H-     C-     H
>>    :
>>   43    41    42                                 ;     H-     O-     H
>>   46    44    45                                 ;     H-     O-     H
>> 
>> } 
>> 
>> I tried other input files with changing O.3 to (O.spc and H.spc) and (O.t3p and H.t3p) ,
>> but force field types of oxygen in H2O were not read. 
>> 
>> Why this problem was occurred? 
>> Should I fix this topology file? 
>> 
>> Could you tell me this problem solution, please?
> 
> 
> Edit your input so that you only give the molecule of interest without the waters.
> 
> Your starting file has two waters and a ligand in it.  topolbuild is designed to
> generate a topology from a file that contains one molecule.  Water topologies are
> already provided for each force field and do not need to be generated with topolbuild
> Thus, you should never include waters in the file submitted to topolbuild
> For this same reason, the special oxygen and hydrogen types used for water topologies
> are not included in the topolbuild files.  Thus, for OPLSAA, where spc.itp specifies
> opls_111 for water oxygen, and opls_112 for water hydrogen, neither is provided in
> topolbuild.  
> 
> 
> 
> -- 
> Bruce D. Ray, Ph.D.
> Associate Scientist
> IUPUI
> Physics Dept.
> 402 N. Blackford St., Rm. LD-061
> Indianapolis, IN  46202
> 
> 
> -- 
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