Figure 7

Local curvature, κ ( ŝ , t ). (a) Curvature across molecule for n = 72 at a stable low temperature (50 K). The curvature across the molecule is approximately constant (with thermal fluctuations); average, approximately 0.27 Å^-1. (b) At a higher temperature (T = 200 K), the structure is unstable and undergoes unfolding. Unfolding induces localized increases in curvature resulting in large peaks (к → 0.5 Å^-1) for sections of the molecule length. Once sufficient unfolding occurs, the structure approaches a homogeneous, unfolded state (κ ≈ 0.12 Å^-1). (c) Curvature across molecule for n = 144 at a stable low temperature (300 K). Again, the curvature across the molecule is approximately constant; average, approximately 0.11 Å^-1. (d) At a higher temperature (T = 725 K), the longer structure is unstable and undergoes unfolding. Again, unfolding induces localized increases in curvature resulting in large peaks (к → 0.3 Å^-1) for sections of the molecule length. Once sufficient unfolding occurs, the structure approaches a homogeneous, unfolded state (κ ≈ 0.06 Å^-1).