[gmx-users] Conversion Amber to Gromacs
Hello GMX users/developers, we are trying to add the Amber lipids17 forcefield to the Amber99 forcefield implemented in Gromacs. We are a little bit lost on the torsion parameters: how to convert the constant from Amber to Gromacs? Thank you in advance! Elisa -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org.
[gmx-users] Conversion Amber to Gromacs
Hello Elisa, "J'arrive après la bataille" To be sure that you have correct Amber parameters for GROMACS, you could also use the acpype suite*. This suite converts Amber params in gromacs format. The program generates the (non)ffbonded.itp and top files in gromacs format from the Amber's LeaP tool. It also provides some gromacs and Amber files to perform and a single point energy to test if the conversion is correctly done. I used successfully this code to convert the Amber lipid14 params for POPC lipid in the GROMACS format. *http://www.ccpn.ac.uk/v2-software/software/ACPYPE-folder HTH Stéphane -- Message: 3 Date: Tue, 24 Oct 2017 17:17:08 +0200 From: Elisa Pieri To: gmx-us...@gromacs.org Subject: Re: [gmx-users] Conversion Amber to Gromacs Message-ID: Content-Type: text/plain; charset="UTF-8" Hello again, Thank you very much for your answers, we got to convert everything. We used pdb2gmx with no problems, and the conf.gro file looks fine (on VMD at least). Then, we tried with a simple input file (from http://www.gromacs.org/@api/deki/files/198/=gmx-tutorial.pdf), but grompp reports a fatal error and a few warnings: This is an example of the warnings: WARNING 15 [file ffnonbonded.itp, line 78]: Too few parameters on line (source file /home/people/Downloads/gromacs-5.1.4/src/gromacs/gmxpreprocess/toppush.c, line 338) And this is the fatal error: Program gmx grompp, VERSION 5.1.4 Source code file: /home/people/Downloads/gromacs-5.1.4/src/gromacs/gmxpreprocess/toppush.c, line: 742 Fatal error: Unknown bond_atomtype hE This is one of the new atomtypes we introduced, but we double checked the connectivity and the bonding parameters for hE and it looks fine. Any idea? Should I send you the force field files? Thank you very much in advance, Elisa On Mon, Oct 23, 2017 at 1:53 PM, Mark Abraham wrote: > On Mon, Oct 23, 2017 at 11:10 AM Elisa Pieri > wrote: > > > Hello again, > > > > sorry I wasn't very clear perhaps..we are trying to modify directly the > > ffbonded.itp file (together with all the other interested ones) in the > > Amber94 force field in order to include the Amber Lipids17 force field. > We > > added most of the parameters with no problems (bond equilibrium lengths, > > constants, bending and so on), but we were not able to understand what is > > the conversion factor for torsion parameters between the Amber software > > Suite and Gromacs. I know that in the Amber package, the dihedral force > > constant is expressed in Kcal/mol, but I couldn't understand what are the > > units (and therefore how to convert the parameters) in Gromacs. > > > > Chapter 2 of the reference manual describes the units. Chapter 4 describes > the functional forms, and e.g. tables in chapter 5 fill in the gaps. That > has always been enough for me when converting stuff to and from AMBER > descriptions. > > Mark > > > > Any idea? > > Elisa > > > > On Fri, Oct 20, 2017 at 7:17 PM, p.kartheek > > wrote: > > > > > ParmEd (https://parmed.github.io/ParmEd/html/parmed.html) would be the > > > appropriate software for converting topologies. > > > This is the parm.py script I have employed, supply amber topologies > > > file.prmtop and file.inpcrd as input and amber.save option will give > > > converted gromacs topologies as output. > > > > > > import parmed as pmd > > > #amber = pmd.load_file('prmtop', 'inpcrd') > > > amber = pmd.load_file('new24_ang.prmtop', 'new24_ang.inpcrd') > > > #save a GROMACS topology and GRO file > > > amber.save('new24_ang.top') > > > amber.save('new24_ang.gro') > > > > > > > > > -- > > > P. Kartheek, > > > PhD Candidate, Computational Biophysical Chemistry, > > > Center for Computational Natural Sciences and Bioinformatics, > > > International Institute of Information Technology, > > > Marimuthu Krishan Group, > > > 9701577399, > > > karthee...@research.iiit.ac.in, > > > > > > > > > On Fri, Oct 20, 2017 at 10:30 PM, p.kartheek > > > wrote: > > > > > > > You can do with ParmEd > > > > On Oct 20, 2017 10:07 PM, "Elisa Pieri" > > wrote: > > > > > > > >> Hello GMX users/developers, > > > >> > > > >> we are trying to add the Amber lipids17 forcefield to the Amber99 > > > >> forcefield implemented in Gromacs. We are a little bit lost on the > > > torsion > > > >> para
Re: [gmx-users] Conversion Amber to Gromacs
You can do with ParmEd On Oct 20, 2017 10:07 PM, "Elisa Pieri" wrote: > Hello GMX users/developers, > > we are trying to add the Amber lipids17 forcefield to the Amber99 > forcefield implemented in Gromacs. We are a little bit lost on the torsion > parameters: how to convert the constant from Amber to Gromacs? > > Thank you in advance! > Elisa > -- > Gromacs Users mailing list > > * Please search the archive at http://www.gromacs.org/ > Support/Mailing_Lists/GMX-Users_List before posting! > > * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > > * For (un)subscribe requests visit > https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or > send a mail to gmx-users-requ...@gromacs.org. > -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org.
Re: [gmx-users] Conversion Amber to Gromacs
ParmEd (https://parmed.github.io/ParmEd/html/parmed.html) would be the appropriate software for converting topologies. This is the parm.py script I have employed, supply amber topologies file.prmtop and file.inpcrd as input and amber.save option will give converted gromacs topologies as output. import parmed as pmd #amber = pmd.load_file('prmtop', 'inpcrd') amber = pmd.load_file('new24_ang.prmtop', 'new24_ang.inpcrd') #save a GROMACS topology and GRO file amber.save('new24_ang.top') amber.save('new24_ang.gro') -- P. Kartheek, PhD Candidate, Computational Biophysical Chemistry, Center for Computational Natural Sciences and Bioinformatics, International Institute of Information Technology, Marimuthu Krishan Group, 9701577399, karthee...@research.iiit.ac.in, On Fri, Oct 20, 2017 at 10:30 PM, p.kartheek wrote: > You can do with ParmEd > On Oct 20, 2017 10:07 PM, "Elisa Pieri" wrote: > >> Hello GMX users/developers, >> >> we are trying to add the Amber lipids17 forcefield to the Amber99 >> forcefield implemented in Gromacs. We are a little bit lost on the torsion >> parameters: how to convert the constant from Amber to Gromacs? >> >> Thank you in advance! >> Elisa >> -- >> Gromacs Users mailing list >> >> * Please search the archive at http://www.gromacs.org/Support >> /Mailing_Lists/GMX-Users_List before posting! >> >> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists >> >> * For (un)subscribe requests visit >> https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or >> send a mail to gmx-users-requ...@gromacs.org. >> > -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org.
Re: [gmx-users] Conversion Amber to Gromacs
Hello again, sorry I wasn't very clear perhaps..we are trying to modify directly the ffbonded.itp file (together with all the other interested ones) in the Amber94 force field in order to include the Amber Lipids17 force field. We added most of the parameters with no problems (bond equilibrium lengths, constants, bending and so on), but we were not able to understand what is the conversion factor for torsion parameters between the Amber software Suite and Gromacs. I know that in the Amber package, the dihedral force constant is expressed in Kcal/mol, but I couldn't understand what are the units (and therefore how to convert the parameters) in Gromacs. Any idea? Elisa On Fri, Oct 20, 2017 at 7:17 PM, p.kartheek wrote: > ParmEd (https://parmed.github.io/ParmEd/html/parmed.html) would be the > appropriate software for converting topologies. > This is the parm.py script I have employed, supply amber topologies > file.prmtop and file.inpcrd as input and amber.save option will give > converted gromacs topologies as output. > > import parmed as pmd > #amber = pmd.load_file('prmtop', 'inpcrd') > amber = pmd.load_file('new24_ang.prmtop', 'new24_ang.inpcrd') > #save a GROMACS topology and GRO file > amber.save('new24_ang.top') > amber.save('new24_ang.gro') > > > -- > P. Kartheek, > PhD Candidate, Computational Biophysical Chemistry, > Center for Computational Natural Sciences and Bioinformatics, > International Institute of Information Technology, > Marimuthu Krishan Group, > 9701577399, > karthee...@research.iiit.ac.in, > > > On Fri, Oct 20, 2017 at 10:30 PM, p.kartheek > wrote: > > > You can do with ParmEd > > On Oct 20, 2017 10:07 PM, "Elisa Pieri" wrote: > > > >> Hello GMX users/developers, > >> > >> we are trying to add the Amber lipids17 forcefield to the Amber99 > >> forcefield implemented in Gromacs. We are a little bit lost on the > torsion > >> parameters: how to convert the constant from Amber to Gromacs? > >> > >> Thank you in advance! > >> Elisa > >> -- > >> Gromacs Users mailing list > >> > >> * Please search the archive at http://www.gromacs.org/Support > >> /Mailing_Lists/GMX-Users_List before posting! > >> > >> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > >> > >> * For (un)subscribe requests visit > >> https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or > >> send a mail to gmx-users-requ...@gromacs.org. > >> > > > -- > Gromacs Users mailing list > > * Please search the archive at http://www.gromacs.org/ > Support/Mailing_Lists/GMX-Users_List before posting! > > * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > > * For (un)subscribe requests visit > https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or > send a mail to gmx-users-requ...@gromacs.org. > -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org.
Re: [gmx-users] Conversion Amber to Gromacs
Hi, The multiplicity/periodicity is the same but always positive in GROMACS. Kd in GROMACS is the AMBER value multiplied by 4.184 then divided by IDIVF (the entry after names in AMBER file). The phase is the same. For more info on why see ambermd.org/formats.html#parm.dat Cheers Tom On 23/10/17 10:09, Elisa Pieri wrote: Hello again, sorry I wasn't very clear perhaps..we are trying to modify directly the ffbonded.itp file (together with all the other interested ones) in the Amber94 force field in order to include the Amber Lipids17 force field. We added most of the parameters with no problems (bond equilibrium lengths, constants, bending and so on), but we were not able to understand what is the conversion factor for torsion parameters between the Amber software Suite and Gromacs. I know that in the Amber package, the dihedral force constant is expressed in Kcal/mol, but I couldn't understand what are the units (and therefore how to convert the parameters) in Gromacs. Any idea? Elisa On Fri, Oct 20, 2017 at 7:17 PM, p.kartheek wrote: ParmEd (https://parmed.github.io/ParmEd/html/parmed.html) would be the appropriate software for converting topologies. This is the parm.py script I have employed, supply amber topologies file.prmtop and file.inpcrd as input and amber.save option will give converted gromacs topologies as output. import parmed as pmd #amber = pmd.load_file('prmtop', 'inpcrd') amber = pmd.load_file('new24_ang.prmtop', 'new24_ang.inpcrd') #save a GROMACS topology and GRO file amber.save('new24_ang.top') amber.save('new24_ang.gro') -- P. Kartheek, PhD Candidate, Computational Biophysical Chemistry, Center for Computational Natural Sciences and Bioinformatics, International Institute of Information Technology, Marimuthu Krishan Group, 9701577399, karthee...@research.iiit.ac.in, On Fri, Oct 20, 2017 at 10:30 PM, p.kartheek wrote: You can do with ParmEd On Oct 20, 2017 10:07 PM, "Elisa Pieri" wrote: Hello GMX users/developers, we are trying to add the Amber lipids17 forcefield to the Amber99 forcefield implemented in Gromacs. We are a little bit lost on the torsion parameters: how to convert the constant from Amber to Gromacs? Thank you in advance! Elisa -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support /Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org. -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/ Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org. -- Dr Thomas Piggot Visiting Fellow University of Southampton, UK. -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org.
Re: [gmx-users] Conversion Amber to Gromacs
On Mon, Oct 23, 2017 at 11:10 AM Elisa Pieri wrote: > Hello again, > > sorry I wasn't very clear perhaps..we are trying to modify directly the > ffbonded.itp file (together with all the other interested ones) in the > Amber94 force field in order to include the Amber Lipids17 force field. We > added most of the parameters with no problems (bond equilibrium lengths, > constants, bending and so on), but we were not able to understand what is > the conversion factor for torsion parameters between the Amber software > Suite and Gromacs. I know that in the Amber package, the dihedral force > constant is expressed in Kcal/mol, but I couldn't understand what are the > units (and therefore how to convert the parameters) in Gromacs. > Chapter 2 of the reference manual describes the units. Chapter 4 describes the functional forms, and e.g. tables in chapter 5 fill in the gaps. That has always been enough for me when converting stuff to and from AMBER descriptions. Mark > Any idea? > Elisa > > On Fri, Oct 20, 2017 at 7:17 PM, p.kartheek > wrote: > > > ParmEd (https://parmed.github.io/ParmEd/html/parmed.html) would be the > > appropriate software for converting topologies. > > This is the parm.py script I have employed, supply amber topologies > > file.prmtop and file.inpcrd as input and amber.save option will give > > converted gromacs topologies as output. > > > > import parmed as pmd > > #amber = pmd.load_file('prmtop', 'inpcrd') > > amber = pmd.load_file('new24_ang.prmtop', 'new24_ang.inpcrd') > > #save a GROMACS topology and GRO file > > amber.save('new24_ang.top') > > amber.save('new24_ang.gro') > > > > > > -- > > P. Kartheek, > > PhD Candidate, Computational Biophysical Chemistry, > > Center for Computational Natural Sciences and Bioinformatics, > > International Institute of Information Technology, > > Marimuthu Krishan Group, > > 9701577399, > > karthee...@research.iiit.ac.in, > > > > > > On Fri, Oct 20, 2017 at 10:30 PM, p.kartheek > > wrote: > > > > > You can do with ParmEd > > > On Oct 20, 2017 10:07 PM, "Elisa Pieri" > wrote: > > > > > >> Hello GMX users/developers, > > >> > > >> we are trying to add the Amber lipids17 forcefield to the Amber99 > > >> forcefield implemented in Gromacs. We are a little bit lost on the > > torsion > > >> parameters: how to convert the constant from Amber to Gromacs? > > >> > > >> Thank you in advance! > > >> Elisa > > >> -- > > >> Gromacs Users mailing list > > >> > > >> * Please search the archive at http://www.gromacs.org/Support > > >> /Mailing_Lists/GMX-Users_List before posting! > > >> > > >> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > > >> > > >> * For (un)subscribe requests visit > > >> https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or > > >> send a mail to gmx-users-requ...@gromacs.org. > > >> > > > > > -- > > Gromacs Users mailing list > > > > * Please search the archive at http://www.gromacs.org/ > > Support/Mailing_Lists/GMX-Users_List before posting! > > > > * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > > > > * For (un)subscribe requests visit > > https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or > > send a mail to gmx-users-requ...@gromacs.org. > > > -- > Gromacs Users mailing list > > * Please search the archive at > http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before > posting! > > * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > > * For (un)subscribe requests visit > https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or > send a mail to gmx-users-requ...@gromacs.org. > -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org.
Re: [gmx-users] Conversion Amber to Gromacs
Hello again, Thank you very much for your answers, we got to convert everything. We used pdb2gmx with no problems, and the conf.gro file looks fine (on VMD at least). Then, we tried with a simple input file (from http://www.gromacs.org/@api/deki/files/198/=gmx-tutorial.pdf), but grompp reports a fatal error and a few warnings: This is an example of the warnings: WARNING 15 [file ffnonbonded.itp, line 78]: Too few parameters on line (source file /home/people/Downloads/gromacs-5.1.4/src/gromacs/gmxpreprocess/toppush.c, line 338) And this is the fatal error: Program gmx grompp, VERSION 5.1.4 Source code file: /home/people/Downloads/gromacs-5.1.4/src/gromacs/gmxpreprocess/toppush.c, line: 742 Fatal error: Unknown bond_atomtype hE This is one of the new atomtypes we introduced, but we double checked the connectivity and the bonding parameters for hE and it looks fine. Any idea? Should I send you the force field files? Thank you very much in advance, Elisa On Mon, Oct 23, 2017 at 1:53 PM, Mark Abraham wrote: > On Mon, Oct 23, 2017 at 11:10 AM Elisa Pieri > wrote: > > > Hello again, > > > > sorry I wasn't very clear perhaps..we are trying to modify directly the > > ffbonded.itp file (together with all the other interested ones) in the > > Amber94 force field in order to include the Amber Lipids17 force field. > We > > added most of the parameters with no problems (bond equilibrium lengths, > > constants, bending and so on), but we were not able to understand what is > > the conversion factor for torsion parameters between the Amber software > > Suite and Gromacs. I know that in the Amber package, the dihedral force > > constant is expressed in Kcal/mol, but I couldn't understand what are the > > units (and therefore how to convert the parameters) in Gromacs. > > > > Chapter 2 of the reference manual describes the units. Chapter 4 describes > the functional forms, and e.g. tables in chapter 5 fill in the gaps. That > has always been enough for me when converting stuff to and from AMBER > descriptions. > > Mark > > > > Any idea? > > Elisa > > > > On Fri, Oct 20, 2017 at 7:17 PM, p.kartheek > > wrote: > > > > > ParmEd (https://parmed.github.io/ParmEd/html/parmed.html) would be the > > > appropriate software for converting topologies. > > > This is the parm.py script I have employed, supply amber topologies > > > file.prmtop and file.inpcrd as input and amber.save option will give > > > converted gromacs topologies as output. > > > > > > import parmed as pmd > > > #amber = pmd.load_file('prmtop', 'inpcrd') > > > amber = pmd.load_file('new24_ang.prmtop', 'new24_ang.inpcrd') > > > #save a GROMACS topology and GRO file > > > amber.save('new24_ang.top') > > > amber.save('new24_ang.gro') > > > > > > > > > -- > > > P. Kartheek, > > > PhD Candidate, Computational Biophysical Chemistry, > > > Center for Computational Natural Sciences and Bioinformatics, > > > International Institute of Information Technology, > > > Marimuthu Krishan Group, > > > 9701577399, > > > karthee...@research.iiit.ac.in, > > > > > > > > > On Fri, Oct 20, 2017 at 10:30 PM, p.kartheek > > > wrote: > > > > > > > You can do with ParmEd > > > > On Oct 20, 2017 10:07 PM, "Elisa Pieri" > > wrote: > > > > > > > >> Hello GMX users/developers, > > > >> > > > >> we are trying to add the Amber lipids17 forcefield to the Amber99 > > > >> forcefield implemented in Gromacs. We are a little bit lost on the > > > torsion > > > >> parameters: how to convert the constant from Amber to Gromacs? > > > >> > > > >> Thank you in advance! > > > >> Elisa > > > >> -- > > > >> Gromacs Users mailing list > > > >> > > > >> * Please search the archive at http://www.gromacs.org/Support > > > >> /Mailing_Lists/GMX-Users_List before posting! > > > >> > > > >> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > > > >> > > > >> * For (un)subscribe requests visit > > > >> https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users > or > > > >> send a mail to gmx-users-requ...@gromacs.org. > > > >> > > > > > > > -- > > > Gromacs Users mailing list > > > > > > * Please search the archive at http://www.gromacs.org/ > > > Support/Mailing_Lists/GMX-Users_List before posting! > > > > > > * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > > > > > > * For (un)subscribe requests visit > > > https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or > > > send a mail to gmx-users-requ...@gromacs.org. > > > > > -- > > Gromacs Users mailing list > > > > * Please search the archive at > > http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before > > posting! > > > > * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists > > > > * For (un)subscribe requests visit > > https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or > > send a mail to gmx-users-requ...@gromacs.org. > > > -- > Gromacs Users mailing list > > * Please search the archive at http://www.gromacs.org/
Re: [gmx-users] Conversion Amber to Gromacs
Please, get it here svn checkout http://ccpn.svn.sourceforge.net/svnroot/ccpn/branches/ stable/ccpn/python/acpype acpype Interestingly, but Google code still holds the correct information too: https://code.google.com/archive/p/acpype/ On 24 October 2017 at 18:34, ABEL Stephane wrote: > Hello Elisa, > > "J'arrive après la bataille" To be sure that you have correct Amber > parameters for GROMACS, you could also use the acpype suite*. This suite > converts Amber params in gromacs format. The program generates the > (non)ffbonded.itp and top files in gromacs format from the Amber's LeaP > tool. It also provides some gromacs and Amber files to perform and a single > point energy to test if the conversion is correctly done. > > I used successfully this code to convert the Amber lipid14 params for > POPC lipid in the GROMACS format. > > *http://www.ccpn.ac.uk/v2-software/software/ACPYPE-folder > > HTH > > Stéphane > > -- > > Message: 3 > Date: Tue, 24 Oct 2017 17:17:08 +0200 > From: Elisa Pieri > To: gmx-us...@gromacs.org > Subject: Re: [gmx-users] Conversion Amber to Gromacs > Message-ID: > gmail.com> > Content-Type: text/plain; charset="UTF-8" > > Hello again, > > Thank you very much for your answers, we got to convert everything. We used > pdb2gmx with no problems, and the conf.gro file looks fine (on VMD at > least). Then, we tried with a simple input file (from > http://www.gromacs.org/@api/deki/files/198/=gmx-tutorial.pdf), but grompp > reports a fatal error and a few warnings: > > This is an example of the warnings: > WARNING 15 [file ffnonbonded.itp, line 78]: Too few parameters on line > (source file > /home/people/Downloads/gromacs-5.1.4/src/gromacs/gmxpreprocess/toppush.c, > line 338) > > And this is the fatal error: > Program gmx grompp, VERSION 5.1.4 > Source code file: > /home/people/Downloads/gromacs-5.1.4/src/gromacs/gmxpreprocess/toppush.c, > line: 742 > Fatal error: Unknown bond_atomtype hE > > This is one of the new atomtypes we introduced, but we double checked the > connectivity and the bonding parameters for hE and it looks fine. Any idea? > Should I send you the force field files? > > Thank you very much in advance, > Elisa > > On Mon, Oct 23, 2017 at 1:53 PM, Mark Abraham > wrote: > > > On Mon, Oct 23, 2017 at 11:10 AM Elisa Pieri > > wrote: > > > > > Hello again, > > > > > > sorry I wasn't very clear perhaps..we are trying to modify directly the > > > ffbonded.itp file (together with all the other interested ones) in the > > > Amber94 force field in order to include the Amber Lipids17 force field. > > We > > > added most of the parameters with no problems (bond equilibrium > lengths, > > > constants, bending and so on), but we were not able to understand what > is > > > the conversion factor for torsion parameters between the Amber software > > > Suite and Gromacs. I know that in the Amber package, the dihedral force > > > constant is expressed in Kcal/mol, but I couldn't understand what are > the > > > units (and therefore how to convert the parameters) in Gromacs. > > > > > > > Chapter 2 of the reference manual describes the units. Chapter 4 > describes > > the functional forms, and e.g. tables in chapter 5 fill in the gaps. That > > has always been enough for me when converting stuff to and from AMBER > > descriptions. > > > > Mark > > > > > > > Any idea? > > > Elisa > > > > > > On Fri, Oct 20, 2017 at 7:17 PM, p.kartheek > > > wrote: > > > > > > > ParmEd (https://parmed.github.io/ParmEd/html/parmed.html) would be > the > > > > appropriate software for converting topologies. > > > > This is the parm.py script I have employed, supply amber topologies > > > > file.prmtop and file.inpcrd as input and amber.save option will give > > > > converted gromacs topologies as output. > > > > > > > > import parmed as pmd > > > > #amber = pmd.load_file('prmtop', 'inpcrd') > > > > amber = pmd.load_file('new24_ang.prmtop', 'new24_ang.inpcrd') > > > > #save a GROMACS topology and GRO file > > > > amber.save('new24_ang.top') > > > > amber.save('new24_ang.gro') > > > > > > > > > > > > -- > > > > P. Kartheek, > > > > PhD Candidate, Computational Biophysical Chemistry, &