Dear Gromacs friends,
I am trying to understand more on the "Steepest Descents" so that I can decide if I need to better minimise the system by reducing the "emtol" or increasing the "nsteps", or other ways. The prompt is shown in the end. My understanding is, the algorithm randomly chooses a starting atom in the system (in my case the 41651th atom), it tries to change its conformation so as to yield lower "Epot" and "Fmax". Then it moves to the second atom, with "Dmax" distance from the first atom, and conducts the conformation change. It keeps moving around until the "Fmax" is lower than the "emtol", or the maximum steps has finished, or there is no more improvement. Please correct my understanding if possible. Basically, can we optimise the minimisation parameters simply based on the prompt (e.g. Dmax, Epot, Fmax, atom)? Cheng Steepest Descents: Tolerance (Fmax) = 1.00000e+01 Number of steps = 10000 Step= 0, Dmax= 1.0e-02 nm, Epot= -1.92831e+06 Fmax= 1.63594e+03, atom= 41651 Step= 1, Dmax= 1.0e-02 nm, Epot= -1.95056e+06 Fmax= 8.94326e+02, atom= 2170 Step= 2, Dmax= 1.2e-02 nm, Epot= -1.98293e+06 Fmax= 4.67586e+02, atom= 73626 ... ... Step= 9998, Dmax= 2.3e-02 nm, Epot= -2.38236e+06 Fmax= 5.07179e+02, atom= 33278 Step= 9999, Dmax= 1.1e-02 nm, Epot= -2.38236e+06 Fmax= 1.74071e+02, atom= 33278 Step=10000, Dmax= 1.4e-02 nm, Epot= -2.38236e+06 Fmax= 2.22063e+02, atom= 33278 Energy minimization reached the maximum number of steps before the forces reached the requested precision Fmax < 10. writing lowest energy coordinates. Steepest Descents did not converge to Fmax < 10 in 10001 steps. Potential Energy = -2.3823640e+06 Maximum force = 2.2206276e+02 on atom 33278 Norm of force = 1.2667693e+00 -- 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.
