We also used an in-house script, as described previously , which incorporates symmetry in the cluster analyses. This second clustering method, which used an RMSD value of 1 Å, was used to cluster similar snapshots from the T-REMD trajectory (Script S1). All the predicted clusters are based on this second method. While analyzing the T-REMD trajectory performed on 2×2 GG/GG, only the clusters observed over 1% are further analyzed. In order to test if the calculated percentages are converged in the T-REMD trajectory, an in-house code (Script S2) was utilized.