In a 2D grid of REMD simulations, we varied the sidechain energetic parameter ε S and sidechain size parameter σ S . In each case, results were generated from 200 ns trajectories with constant entropy increase temperature spacing, as described above, following a preliminary 50 ns simulation with logarithmic temperature spacing. In addition to the fixed parameters specified in Section 3.1, the following bonded parameters were used, based on the geometry of the energy-minimized helix and reasonable estimates of force constants from preliminary simulations: k a = 100/rad 2 , k t = 3. Tuning the sidechain Lennard-Jones parameters allows for fine control over the foldamer melting point (stability), height and width of the heat capacity curve (cooperativity), and even the helix geometry itself (pitch, radius). The heat capacity curves and corresponding native contacts curves for various combinations of σ S and ε S values are presented in Figure . Helix stability (melting point) increases with sidechain interaction strength (ε S ), and decreases with increasing sidechain size (σ S ) due to stretching of the helical backbone. In particular, bulkier sidechain beads lead to higher pitch and slightly wider radius of the helical backbone. This helix stretching effect is most evident in the case of strong sidechain interactions (large ε S ). Figure shows a representation of the ensemble of folded structures, determined from DBSCAN clustering, for three different values of σ S and with ε S = 4.