[gmx-users] Desired density - genbox

[Steven Neumann]

Dear Gmx Users,

I am trying to obtain given density for my system for a given molecule
- its a cubic box of 5 nm in dimension.

I calculated that I need 850 molecules to get the density of 500 g/mol
In my box there is already 1 molecule so I try:

genbox -cp Box.pdb -ci molecule.pdb -nmol 849 -o BoxMol.pdb



Added 819 molecules (out of 849 requested)
Output configuration contains 9020 atoms in 820 residues
Volume                 :         125 (nm^3)
Density                :     480.336 (g/l)
Number of SOL molecules:      0

How can I add 30 more molecules using gromacs? I want to avoid adding
it manually.

Thank you,

Steven