Hello,<br><br>I am trying to restrain Na+ to a specific position (0.487, 1.620, 1.620) of my box of dimensions 3.2418 X 3.2418 X 3.2418 nm. The box is also full of 253 THF molecules. I added the following to the bottom of my .itp file:<br>
<br>#ifdef POSRES<br>#include "posre_Na+.itp"<br>#endif<br><br>I wrote the posre_Na+.itp file myself, it just includes the position restraints for Na+, which is atom 1 in my .gro file, and my posre_Na+.itp file deals with atom 1. The force constants are all 1000.<br>
<br>Under the .mdp file, I also made sure that define = -DPOSRES.<br><br>I get no errors when things run, but I do get my Na+ moving around. After I do energy minimization, Na+ ends up at the position (0.373, 1.504, 1.226). I also do not notice anything about position restraints appearing in my .log file afterwards.<br>
<br>I really appreciate the help.<br><br>Thank you,<br>Jenny<br>