Reading system_test.gro...
Read 'GROningen MAchine for Chemical SImulation', 23710 atoms
Analyzing pdb file
There are 1 chains and 1 blocks of water and 14570 residues with 23710 atoms

  chain  #res #atoms
  1 '-' 10000  10000  
  2 '-'  4570  13710  (only water)


Select the Force Field:
 0: Gromacs Forcefield (see manual)
 1: Gromacs Forcefield with all hydrogens (proteins only)
 2: GROMOS96 43a1 Forcefield (official distribution)
 3: GROMOS96 43b1 Vacuum Forcefield (official distribution)
 4: GROMOS96 43a2 Forcefield (development) (improved alkane dihedrals)
 5: OPLS-AA/L all-atom force field (2001 aminoacid dihedrals)
Using ffG43a1 force field
Reading residue database... (ffG43a1)
Processing chain 1 (10000 atoms, 10000 residues)
Opening library file /usr/local/gromacs/share/top/xlateat.dat
13 out of 13 lines of xlateat.dat converted succesfully

Opening library file /usr/local/gromacs/share/top/aminoacids.dat
No occupancies in system_test.gro
Opening library file /usr/local/gromacs/share/top/FF.dat
2
Opening library file /usr/local/gromacs/share/top/ffG43a1.atp
Atomtype 47
Opening library file /usr/local/gromacs/share/top/ffG43a1.rtp
Using default value - not generating all possible dihedrals
Using default value - excluding 3 bonded neighbors
Residue 95
Sorting it all out...
Opening library file /usr/local/gromacs/share/top/ffG43a1.hdb
Opening library file /usr/local/gromacs/share/top/ffG43a1-n.tdb
Opening library file /usr/local/gromacs/share/top/ffG43a1-c.tdb

Back Off! I just backed up water.top to ./#water.top.1#
Opening library file /usr/local/gromacs/share/top/specbond.dat
5 out of 5 lines of specbond.dat converted succesfully
There are 0 donors and 4999 acceptors
There are 0 hydrogen bonds
Fatal error: Residue '' not found in residue topology database