Re: [gmx-users] Question about topology construction.

2014-03-21 Thread sujith ks
Hello Justin, Thanks for the response. In the EMP2 model the bond angle potential is of the harmonic form with the equilibrium angle 180. The only way I could include this in the .itp was though [angles]. The other two options [angle_restraints] and [angle_restraints_z] has a different form for

Re: [gmx-users] A question about "blowing up"

2014-03-01 Thread sujith ks
Hello Justin, I performed energy minimization , the way you performed for the free energy calculation for the methane-water system in the tutorial. In the first step steepest descent was used followed by l-bfgs. The emtol (force) was set to 10 kj/mol/nm. The final results can be summerized as:

Re: [gmx-users] Dubious results with NPT

2014-02-23 Thread sujith ks
Hello, Thank you both for the comments. I am using gromos96 forcefield . I read a little bit and as you said the nonbonded cutoff has to be higher. The tau_p=5ps was chosen , since the manual mentions that the value has to be raised by 4-5 times on going from berendsen to parrinello-rahman bar