<P>
<BR>
Hi everyone,<BR>
I am facing a peculiar problem with "genion". I have a system with overall charge <BR>
0f +3. <BR>
I want genion to add enough ions to make the cocncentration 10 micromoles/litre.<BR>
When I give the command <BR>
genion -s em.tpr -o ions.gro -conc 0.00001 -pname NA+ -nname CL- -p topol.top ,<BR>
<BR>
it gives the message<BR>
"No ions to add and no potential to calculate."<BR>
If I use the "-neutral" option with the "genion " command, it adds 3 CL- ions.<BR>
<BR>
However it works perfectly fine when I specify the concentration to be 0.15 Moles/litre.<BR>
The number of ions added to the system matches with calculations done manually.<BR>
<BR>
However I can't figure out what is the problem with the low concentration command.<BR>
<BR>
Any suggestion will be extremely heplful.<BR>
Thanks in advance<BR>
Sarbani
</P>
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