Hi Yihua Zhou,
Step Time Lambda > 0 0.00000 0.00000 > > Energies (kJ/mol) > Bond G96Angle Proper Dih. LJ (SR) Coulomb (SR) > 4.19801e+05 1.40206e+03 3.49599e+03 8.36580e+20 8.17307e+04 > Potential Kinetic En. Total Energy Temperature Pressure (bar) > 8.36580e+20 inf inf inf inf > > This is the relevant information from your log file. As you can see there are several terms at infinite. That indicates there's a problem. The short-range Lennard-Jones is quite high. Probably you have overlaps in your system. Did you check the system before running, also making sure that the PBC are set correctly and not cause overlaps? Cheers, Tsjerk -- Tsjerk A. Wassenaar, Ph.D. post-doctoral researcher Biocomputing Group Department of Biological Sciences 2500 University Drive NW Calgary, AB T2N 1N4 Canada -- gmx-users mailing list gmx-users@gromacs.org http://lists.gromacs.org/mailman/listinfo/gmx-users * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/Search before posting! * Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org. * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists