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vladislavivanistsev / RTIL-FF

Gromacs Topology Files for common Ionic Liquids
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Energy minimization is giving negetive potential energy #13

Open abanerjee123 opened 7 years ago

abanerjee123 commented 7 years ago

Hi Thanks for IL topologies. I was just trying to simulate a system bmimpf6. The problem is that if I do energy minimization, it is giving negative potential energy. this is the minimization script. ; minim.mdp - used as input into grompp to generate em.tpr integrator = steep ; Algorithm (steep = steepest descent minimization) emtol = 100.0 ; Stop minimization when the maximum force < 1000.0 kJ/mol/nm emstep = 0.02 ; Energy step size nsteps = 50000 ; Maximum number of (minimization) steps to perform

; Parameters describing how to find the neighbors of each atom and how to calculate the interactions nstlist = 10 ; Frequency to update the neighbor list and long range forces cutoff-scheme = Verlet ns_type = grid ; Method to determine neighbor list (simple, grid) coulombtype = PME ; Treatment of long range electrostatic interactions rcoulomb = 0.8 ; Short-range electrostatic cut-off rvdw = 0.8 ; Short-range Van der Waals cut-off pbc = xyz ; Periodic Boundary Conditions (yes/no)

vladislavivanistsev commented 7 years ago

You are welcome. The negative potential energy should originate from the Coulomb type interaction between anions and cations. Check the relative contributions of Coulomb and Lennard-Jones energies.

abanerjee123 commented 7 years ago

Extremely sorry. Its giving positive PE. I don't know why.

On 17-Apr-2017 4:27 PM, "Vladilsav Ivanistsev" notifications@github.com wrote:

You are welcome. The negative potential energy should originate from the Coulomb type interaction between anions and cations. Check the relative contributions of Coulomb and Lennard-Jones energies.

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/vladislavivanistsev/RTIL-FF/issues/13#issuecomment-294451738, or mute the thread https://github.com/notifications/unsubscribe-auth/AC3kyeNfn23Zf7GC4hJzKu6Vp2H2eyDXks5rw0WdgaJpZM4M-iaX .

vladislavivanistsev commented 7 years ago

That is more interesting. I would like to see all inputs. Please send it to my e-mail: vi@ut.ee.

vladislavivanistsev commented 7 years ago

Any updates from you? Should this be closed?