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Modification of the dihedral parameters

The files for this exercise are in /cluster/home03/matl/danielep/LECTURE2/EXERCISE_2.3 The relevant files are ff_ij and inp_ff.templ, respectively the script to generate the “path” and the input file model for cp2k.

In this exercise, you are requested to start from the results of exercise 2, and perform the following steps

Choose (use vmd to measure the angles) two configurations A and B from the previously optimized grid, close to the two minima
Remove the “restraint” part and perform a “free” geometry optimization
once the two optimum geometries are obtained, open the two optimized configurations with vmd and mark the two angles
Substitute the values of the angles in the following script, and generate a line (again using restraints to fix the dihedrals along this line)
In this way you will obtain an energy profile joining the two minima (would it be an idea to do a nudged elastic band?)
Now, you can create a new directory, and use a different potential file where a dihedral angle is increased or decreased. How will the line profile change? Why?