4 0.6 0.8 1.0 -o replica_path_free.png
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<p>to plot the path of the first few &lambda;-values. It should look something like this.<br> <img src="replica_path_free.png" width="33%" height="40%" alt="" /><br> as is clear, these replicas were not able to traverse the full &lambda;-space within the simulation time. Also the replicas starting with &lambda;=1.0 or 0.0 did not exchange very much at all. Hence, the replica exchange was not fully efficient.</p>
<p>Now, we will estimate the free energy. We will 