[gmx-users] RE: Test Particle Insertion

Phan, Anh T. anhphan at ou.edu
Fri Jun 21 17:28:28 CEST 2013


Dear Rajesh and Damas,
Thank you for your help.
I will try now.

Thanks again.
Sincerely,
Anh

-----Original Message-----
From: gmx-users-bounces at gromacs.org [mailto:gmx-users-bounces at gromacs.org] On Behalf Of gmx-users-request at gromacs.org
Sent: Thursday, June 20, 2013 10:19 PM
To: gmx-users at gromacs.org
Subject: gmx-users Digest, Vol 110, Issue 115

Send gmx-users mailing list submissions to
	gmx-users at gromacs.org

To subscribe or unsubscribe via the World Wide Web, visit
	http://lists.gromacs.org/mailman/listinfo/gmx-users
or, via email, send a message with subject or body 'help' to
	gmx-users-request at gromacs.org

You can reach the person managing the list at
	gmx-users-owner at gromacs.org

When replying, please edit your Subject line so it is more specific than "Re: Contents of gmx-users digest..."


Today's Topics:

   1. Re: Decouple (Justin Lemkul)
   2. Re: Test Particle Insertion (Jo?o M. Damas)
   3. Re: Decouple (Justin Lemkul)
   4. (no subject) (Hari Pandey)
   5. Re: (no subject) (Justin Lemkul)


----------------------------------------------------------------------

Message: 1
Date: Thu, 20 Jun 2013 17:16:29 -0400
From: Justin Lemkul <jalemkul at vt.edu>
Subject: Re: [gmx-users] Decouple
To: Hari Pandey <harichem12 at yahoo.com>,	Discussion list for GROMACS
	users <gmx-users at gromacs.org>
Message-ID: <51C3712D.5030009 at vt.edu>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed



On 6/20/13 5:01 PM, Hari Pandey wrote:
> Hi ,
>
> How do I  solve this problem in GROMACS:
>
> I have a system with 3 part A,B and C
>
> I have to put thermostat for A and C but not for  B.
> Gromacs   display error, what is temperature for B.
>
>
> How do aI decouple part B
>

Per the manual:

"tau-t: [ps]
time constant for coupling (one for each group in tc-grps), -1 means no temperature coupling"

-Justin

--
========================================

Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin

========================================


------------------------------

Message: 2
Date: Fri, 21 Jun 2013 00:29:15 +0100
From: Jo?o M. Damas <jmdamas at itqb.unl.pt>
Subject: Re: [gmx-users] Test Particle Insertion
To: Discussion list for GROMACS users <gmx-users at gromacs.org>
Message-ID:
	<CAN8VxHxcUPN6Q0fTjRURD0e0vjzP-2uzqODBL_NhHLDdt=4RWQ at mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1

Dear Anh,

You need to construct a .tpr file for the mdrun -rerun with:

   - a .gro file with the ligand to be inserted at the end, which _must_ be
   geometrically centered at 0,0,0 ;
   - a matching .top file (which means with the ligand topology
   appropriately inserted) ;
   - a .mdp file with the specific parameters for the tpi algorithm .

Since you happen to have a single particle to insert, that particle's coordinates should be 0,0,0 in the .gro file from grompp (your initial.gro).

Best,
Jo?o


On Thu, Jun 20, 2013 at 8:08 PM, Phan, Anh T. <anhphan at ou.edu> wrote:

> Dear GMX Users,
> My name is Anh Phan, a PhD student at University of Oklahoma.
> I would like to calculate excess chemical potential of one gas 
> molecule in water solvent using Widom test particle insertion with Gromacs.
> In this method, I will insert this gas molecule at a random position 
> in each configuration of the system.
> With Gromacs, I see I can use tpi (integrator = tpi).
> I know I have to add this gas molecule in the topology (topol.top) 
> Also, it is indicated in the manual that insertions are performed 
> nsteps times in each frame at random locations and with random 
> orientiations of the molecule. That is what I desire.
> The question I would like to ask is whether I have to add the 
> specified coordinate of gas molecule in the .gro file at the beginning 
> of running simulation.
> For example, in the initial.gro file
> .....
> 26734SOL     OW45744  21.969   6.237   2.921
> 26734SOL    HW145745  21.969   6.253   3.019
> 26734SOL    HW245746  21.886   6.188   2.895
> 26735SOL     OW45747  15.155   7.211   2.853
> 26735SOL    HW145748  15.220   7.265   2.801
> 26735SOL    HW245749  15.204   7.151   2.916
> 26736SOL     OW45750  24.606   4.896   3.053
> 26736SOL    HW145751  24.594   4.972   2.989
> 26736SOL    HW245752  24.532   4.896   3.120
> 26737INS             X45752        1.000        1.000        1.000 ( Do I
> have to add this line in the initial.gro file)
>
> The command lines
> grompp -f input.mdp -c initial.gro -p topol.top -n index.ndx -o 
> tpi.tpr -maxwarn 2 mdrun -s tpi.tpr -rerun md.trr -x traj.xtc -c 
> final.gro -e init3.ener -g init3.log -deffnm tpi -tpi tpi.xvg -tpid 
> tpid.xvg
>
> I am looking forward to receiving your reply.
> Thank you for your help.
> Sincerely,
> Anh
> --
> gmx-users mailing list    gmx-users at gromacs.org
> http://lists.gromacs.org/mailman/listinfo/gmx-users
> * Please search the archive at
> http://www.gromacs.org/Support/Mailing_Lists/Search before posting!
> * Please don't post (un)subscribe requests to the list. Use the www 
> interface or send it to gmx-users-request at gromacs.org.
> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists
>



--
Jo?o M. Damas
PhD Student
Protein Modelling Group
ITQB-UNL, Oeiras, Portugal
Tel:+351-214469613


------------------------------

Message: 3
Date: Thu, 20 Jun 2013 21:30:29 -0400
From: Justin Lemkul <jalemkul at vt.edu>
Subject: Re: [gmx-users] Decouple
To: Hari Pandey <harichem12 at yahoo.com>,	Discussion list for GROMACS
	users <gmx-users at gromacs.org>
Message-ID: <51C3ACB5.4010202 at vt.edu>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed


Please keep the discussion on the gmx-users mailing list; I am not a private 
tutor.  Comments embedded below.

On 6/20/13 8:35 PM, Hari Pandey wrote:
> Hi Justin,
>   Thanks for last help.
>
> I have following (NVT.mdp) (NPT.mdp)  and (NVE.mdp)   .  I have three parts of
> system, A, B and C.
> I want to put thermostat on A and C and couple the tempereture and do not put
> any thermostat on B.
>
> What I want is: after some ps,  temperature of A and C should be constant (i.e
> reach up to steady state) and  B may not be.
>
> for that My NVT.mdp is:
> ; simulation at 300K and 2 ps is on
>          constraints =all-bonds
>          integrator      =md
>          dt              =0.001 ; ps
>          nsteps          =100000 ; total 100 ps
>          nstcomm         =10
>          nstxout         =1000
>          nstxtcout       =0
>          nstvout         =0
>          nstfout         =0
> nstenergy       =100
>          nstlist         =100

This value of nstlist is much too large.

>          ns_type         =grid
>          rlist           =0.5
>          coulombtype     =pme
>          rcoulomb        =0.5
>          vdwtype         =cut-off
>          rvdw            =0.5

Unless you are using some custom force field that requires 0.5-nm cutoffs, these 
values are incorrect.

>          pme_order       =4
> ewald_rtol      =1e-5
>          optimize_fft    =yes
>          DispCorr        =no
>
> ;Brendsen tempereture coupling is on
>          Tcoupl          = nose-hoover

Nose-Hoover is a poor choice for initial equilibration, especially when 
generating velocities.

>          tau_t           =0.001  -1   0.001

Setting tau_t = dt is a bad idea and grompp should have warned you about this.

>          tc-grps         =A  B   C
>
>          ref_t =750      300       350
>
>
> ;pressure coupling is on
>          Pcoupl          =no
>          Pcoupltype      =isotropic
>          tau_p           =0.5
>          compressibility =1e-5
>          ref_p           =0.5
> ;generate velocities at 300 k i.e. at room tempereture
>          gen_vel         =yes
>          gen_temp        =750  300  350
> gen_seed        =-1
>
> MY NPT.mdp is:
>
> ( here all output control parameters also)
>
> ;Brendsen tempereture coupling is on
> Tcoupl          =nose-hoover
>          tau_t           =1  -1   1
>          tc-grps         =NCALPHA MIDDLE NCNN
>          ref_t           =750  300 350
>
>
>
> ;pressure coupling is on
>          Pcoupl          =Berendsen
>          Pcoupltype      =isotropic
>          tau_p           =0.5
>          compressibility =1e-5
> ref_p           =1
> ;generate velocities at 300 k i.e. at room tempereture
>          gen_vel         =no
>          gen_temp        =750 300 350
>          gen_seed        =-1
>
> MY NVE.mdp is:
> ( here all output control parameters also)
> tc-grps         = A  B  C
>          ref_t           =750 300 300
>          energygrps      = NCALPHA  MIDDLE  NCNN
>          tcoupl         = nose-hoover
>          tau-t          = 1  -1   1

If you're using thermostats, you're not simulating in an NVE ensemble.

> ;pressure coupling is on
>          Pcoupl          =no
>          ;Pcoupltype      =isotropic
>          ;tau_p =0.5
>          ;compressibility =1e-5
>          ;ref_p           =0.5
> ;generate velocities at 300 k i.e. at room tempereture
>          gen_vel         =no
>        ;  gen_temp        =750  300  350
>         ; gen_seed        =-1
>
>
> What I did is:
>
> pdb2gmx - argnew.pdb -o fws.pdb -p  fws.top;
> editconf -f fws.pdb -bt dodecahedron -o fws.pdb -d 1.0;
> grompp-f em.mdp -c fws.pdb -p fws.top -n index.ndx -o em.tpr -maxwarn 5;
> mdrun -deffnm  em -v;
> grompp -f nvt.mdp -c em.gro -p fws.top -n index.ndx  -o nvt.tpr -maxwarn 5;
> mdrun -deffnm nvt -v;
> grompp -f npt.mdp -c nvt.gro -p fws.top -n index.ndx  -o npt.tpr -maxwarn 5;
> mdrun -deffnm npt -v
> grompp -f nve.mdp -c npt.gro -p fws.top -n index.ndx  -o nve.tpr -maxwarn 5;
> mdrun -deffnm nve -v;
>
> g_energy -f nve.edr -s nve.tpr -o F1.xvg
>
>
> But the system do not get equilibrated and A, B has not steady state
> temperature  after   time
>   even 100 ps. please help me, where I did wrong
>

You have numerous issues, listed above.

-Justin

-- 
========================================

Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin

========================================


------------------------------

Message: 4
Date: Thu, 20 Jun 2013 20:11:28 -0700 (PDT)
From: Hari Pandey <harichem12 at yahoo.com>
Subject: [gmx-users] (no subject)
To: "gmx-users at gromacs.org" <gmx-users at gromacs.org>
Message-ID:
	<1371784288.83241.YahooMailNeo at web163006.mail.bf1.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1

Hi all? gromacs users

I have following (NVT.mdp) (NPT.mdp)? and (NVE.mdp)?? .? I have three parts of system, A, B and C.
I want to put thermostat on A and C and couple the tempereture and do not put any thermostat on B.

What I want is: after some ps,? temperature of A and C should be constant (i.e reach up to steady state) and? B may not be.

for that My NVT.mdp is:
; simulation at 300K and 2 ps is on
??????? constraints???? =all-bonds
??????? integrator????? =md
??????? dt????????????? =0.001 ; ps
??????? nsteps????????? =100000 ; total 100 ps
??????? nstcomm???????? =10
??????? nstxout???????? =1000
??????? nstxtcout?????? =0
???????
 nstvout???????? =0
??????? nstfout???????? =0
??????? nstenergy?????? =100
??????? nstlist???????? =100
??????? ns_type???????? =grid
??????? rlist?????????? =0.5
??????? coulombtype???? =pme
??????? rcoulomb??????? =0.5
??????? vdwtype???????? =cut-off
???????
 rvdw??????????? =0.5
??????? pme_order?????? =4
??????? ewald_rtol????? =1e-5
??????? optimize_fft??? =yes
??????? DispCorr??????? =no


;Brendsen tempereture coupling is on
??????? Tcoupl????????? = nose-hoover
??????? tau_t?????????? =0.001?
 -1?? 0.001
??????? tc-grps???????? =A? B ? C

??????? ref_t?????????? =750????? 300?????? 350


;pressure coupling is on
??????? Pcoupl????????? =no
??????? Pcoupltype????? =isotropic
??????? tau_p?????????? =0.5
??????? compressibility =1e-5
??????? ref_p?????????? =0.5
;generate velocities at 300 k i.e. at room
 tempereture
??????? gen_vel???????? =yes
??????? gen_temp??????? =750? 300? 350
??????? gen_seed??????? =-1

MY NPT.mdp is:

( here all output control parameters also)


;Brendsen tempereture coupling is on
??????? Tcoupl????????? =nose-hoover
??????? tau_t?????????? =1? -1?? 1
??????? tc-grps????????
 =NCALPHA MIDDLE NCNN
??????? ref_t?????????? =750? 300 350



;pressure coupling is on
??????? Pcoupl????????? =Berendsen
??????? Pcoupltype????? =isotropic
??????? tau_p?????????? =0.5
??????? compressibility =1e-5
??????? ref_p?????????? =1
;generate velocities at 300 k i.e. at room tempereture
??????? gen_vel???????? =no
???????
 gen_temp??????? =750 300 350
??????? gen_seed??????? =-1

MY NVE.mdp is:
( here all output control parameters also)
? tc-grps???????? = A? B? C
???????
 ref_t?????????? =750 300 300
??????? energygrps????? = NCALPHA? MIDDLE? NCNN
??????? tcoupl???????? = nose-hoover
??????? tau-t????????? = 1? -1?? 1
;pressure coupling is on
??????? Pcoupl????????? =no
??????? ;Pcoupltype????? =isotropic
??????? ;tau_p?????????? =0.5
??????? ;compressibility =1e-5
???????
 ;ref_p?????????? =0.5
;generate velocities at 300 k i.e. at room tempereture
??????? gen_vel???????? =no
????? ;? gen_temp??????? =750? 300? 350
?????? ; gen_seed??????? =-1



What I did is:

pdb2gmx - argnew.pdb -o fws.pdb -p? fws.top;
editconf -f fws.pdb -bt dodecahedron -o fws.pdb -d 1.0;
grompp-f em.mdp -c fws.pdb -p fws.top -n index.ndx -o em.tpr -maxwarn 5;
mdrun -deffnm? em -v;
grompp -f nvt.mdp -c em.gro -p fws.top -n index.ndx? -o nvt.tpr -maxwarn 5;
mdrun -deffnm nvt -v;
grompp -f npt.mdp -c nvt.gro -p fws.top -n index.ndx? -o npt.tpr -maxwarn 5;
mdrun -deffnm npt -v
grompp -f nve.mdp -c npt.gro -p fws.top -n index.ndx? -o nve.tpr -maxwarn 5;
mdrun -deffnm nve -v;

g_energy -f nve.edr -s nve.tpr -o F1.xvg



But the system do not get equilibrated and A, B has not steady state temperature? after?? time
?even 100 ps. please help me, where I did wrong


Thanks for your help




________________________________

------------------------------

Message: 5
Date: Thu, 20 Jun 2013 23:18:07 -0400
From: Justin Lemkul <jalemkul at vt.edu>
Subject: Re: [gmx-users] (no subject)
To: Hari Pandey <harichem12 at yahoo.com>,	Discussion list for GROMACS
	users <gmx-users at gromacs.org>
Message-ID: <51C3C5EF.1010703 at vt.edu>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed


On 6/20/13 11:11 PM, Hari Pandey wrote:
> Hi all  gromacs users
>
> I have following (NVT.mdp) (NPT.mdp)  and (NVE.mdp)   .  I have three parts of system, A, B and C.
> I want to put thermostat on A and C and couple the tempereture and do not put any thermostat on B.
>
> What I want is: after some ps,  temperature of A and C should be constant (i.e reach up to steady state) and  B may not be.
>
> for that My NVT.mdp is:
> ; simulation at 300K and 2 ps is on
>          constraints     =all-bonds
>          integrator      =md
>          dt              =0.001 ; ps
>          nsteps          =100000 ; total 100 ps
>          nstcomm         =10
>          nstxout         =1000
>          nstxtcout       =0
>
>   nstvout         =0
>          nstfout         =0
>          nstenergy       =100
>          nstlist         =100
>          ns_type         =grid
>          rlist           =0.5
>          coulombtype     =pme
>          rcoulomb        =0.5
>          vdwtype         =cut-off
>
>   rvdw            =0.5
>          pme_order       =4
>          ewald_rtol      =1e-5
>          optimize_fft    =yes
>          DispCorr        =no
>
>
> ;Brendsen tempereture coupling is on
>          Tcoupl          = nose-hoover
>          tau_t           =0.001
>   -1   0.001
>          tc-grps         =A  B   C
>
>          ref_t           =750      300       350
>
>
> ;pressure coupling is on
>          Pcoupl          =no
>          Pcoupltype      =isotropic
>          tau_p           =0.5
>          compressibility =1e-5
>          ref_p           =0.5
> ;generate velocities at 300 k i.e. at room
>   tempereture
>          gen_vel         =yes
>          gen_temp        =750  300  350
>          gen_seed        =-1
>
> MY NPT.mdp is:
>
> ( here all output control parameters also)
>
>
> ;Brendsen tempereture coupling is on
>          Tcoupl          =nose-hoover
>          tau_t           =1  -1   1
>          tc-grps
>   =NCALPHA MIDDLE NCNN
>          ref_t           =750  300 350
>
>
>
> ;pressure coupling is on
>          Pcoupl          =Berendsen
>          Pcoupltype      =isotropic
>          tau_p           =0.5
>          compressibility =1e-5
>          ref_p           =1
> ;generate velocities at 300 k i.e. at room tempereture
>          gen_vel         =no
>
>   gen_temp        =750 300 350
>          gen_seed        =-1
>
> MY NVE.mdp is:
> ( here all output control parameters also)
>    tc-grps         = A  B  C
>
>   ref_t           =750 300 300
>          energygrps      = NCALPHA  MIDDLE  NCNN
>          tcoupl         = nose-hoover
>          tau-t          = 1  -1   1
> ;pressure coupling is on
>          Pcoupl          =no
>          ;Pcoupltype      =isotropic
>          ;tau_p           =0.5
>          ;compressibility =1e-5
>
>   ;ref_p           =0.5
> ;generate velocities at 300 k i.e. at room tempereture
>          gen_vel         =no
>        ;  gen_temp        =750  300  350
>         ; gen_seed        =-1
>
>
>
> What I did is:
>
> pdb2gmx - argnew.pdb -o fws.pdb -p  fws.top;
> editconf -f fws.pdb -bt dodecahedron -o fws.pdb -d 1.0;
> grompp-f em.mdp -c fws.pdb -p fws.top -n index.ndx -o em.tpr -maxwarn 5;
> mdrun -deffnm  em -v;
> grompp -f nvt.mdp -c em.gro -p fws.top -n index.ndx  -o nvt.tpr -maxwarn 5;
> mdrun -deffnm nvt -v;
> grompp -f npt.mdp -c nvt.gro -p fws.top -n index.ndx  -o npt.tpr -maxwarn 5;
> mdrun -deffnm npt -v
> grompp -f nve.mdp -c npt.gro -p fws.top -n index.ndx  -o nve.tpr -maxwarn 5;
> mdrun -deffnm nve -v;
>
> g_energy -f nve.edr -s nve.tpr -o F1.xvg
>
>
>
> But the system do not get equilibrated and A, B has not steady state temperature  after   time
>   even 100 ps. please help me, where I did wrong
>

See my previous reply:

http://lists.gromacs.org/pipermail/gmx-users/2013-June/082392.html

-Justin

-- 
========================================

Justin A. Lemkul, Ph.D.
Research Scientist
Department of Biochemistry
Virginia Tech
Blacksburg, VA
jalemkul[at]vt.edu | (540) 231-9080
http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin

========================================


------------------------------

-- 
gmx-users mailing list
gmx-users at gromacs.org
http://lists.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/Search before posting!

End of gmx-users Digest, Vol 110, Issue 115
*******************************************



More information about the gromacs.org_gmx-users mailing list