hi,<br><br>I tried on other system , 4GB ram , core i3 ,64bit processor <br><br><br>; minim.mdp - used as input into grompp to generate em.tpr<br>; Parameters describing what to do, when to stop and what to save<br>integrator = steep ; Algorithm (steep = steepest descent minimization)<br>
emtol = 10.0 ; Stop minimization when the maximum force < 1000.0 kJ/mol/nm<br>emstep = 0.01 ; Energy step size<br>nsteps = 25000 ; Maximum number of (minimization) steps to perform<br>
<br>; Parameters describing how to find the neighbors of each atom and how to calculate the interactions<br>nstlist = 10 ; Frequency to update the neighbor list and long range forces<br>ns_type = grid ; Method to determine neighbor list (simple, grid)<br>
rlist = 1.2 ; Cut-off for making neighbor list (short range forces)<br>coulombtype = Shift ; Treatment of long range electrostatic interactions<br>rcoulomb = 1.2 ; Short-range electrostatic cut-off<br>
rvdw = 1.2 ; Short-range Van der Waals cut-off<br>pbc = xyz ; Periodic Boundary Conditions (yes/no)<br>nstxout = 1<br><br><br><br><br>result''''''''<br>
<br>Steepest Descents:<br> Tolerance (Fmax) = 1.00000e+01<br> Number of steps = 25000<br>Step= 14, Dmax= 1.2e-06 nm, Epot= -nan Fmax= 3.56233e+07, atom= 2455<br>Stepsize too small, or no change in energy.<br>
Converged to machine precision,<br>but not to the requested precision Fmax < 10<br><br>Double precision normally gives you higher accuracy.<br><br>writing lowest energy coordinates.<br><br>Back Off! I just backed up after_em2.gro to ./#after_em2.gro.1#<br>
<br>Steepest Descents converged to machine precision in 15 steps,<br>but did not reach the requested Fmax < 10.<br>Potential Energy = -nan<br>Maximum force = 3.5637456e+07 on atom 2455<br>Norm of force = -nan<br>
<br><br>help me!<br><br><br>shikha<br><br>