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Dear gmx users,<BR>
I am performing one MD simulation of a polymer system using GROMACS-4.0.7. I want to calculate the cohesive energy. According to the definition, cohesive energy can be calculated the difference in energy between the model system with and without pbc. I must perform the two separate simulations on the two systems? Or more convenient, is the procedure below true?<BR>
1. to perform MD simulation (pbc = yes) on the model system with system and to calculate the energies (old energies)<BR>
2. to edit the mdp file line: pbc = no, and to make another tpr file (new tpr file) using this mdp file<BR>
3. to run mdrun -return using the old trr file and the new tpr file as the inputs to calculate the energies (new energies)<BR>
4. to calculate the difference between the old and the new energies<BR>
please give me some hints.<BR>
Best regards,<BR>
<BR>
Chaofu Wu, Dr.<BR>
<A href="mailto:xiaowu759@hotmail.com">xiaowu759@hotmail.com</A><BR>                                            <br /><hr />使用新一代 Windows Live Messenger 轻松交流和共享! <a href='http://www.windowslive.cn/messenger/' target='_new'>立刻下载!</a></body>
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