Polymer Coil-to-Globule Transition

Flory theory balances entropic elasticity and excluded-volume interactions. Excluded volume parameter: v = 1 − 2χ (good solvent χ<0.5, theta χ=0.5, poor χ>0.5). Flory radius: R_F ~ N^ν b where ν=3/5 (good), 1/2 (theta), 1/3 (globule). The simulation shows a self-avoiding walk (good) or collapsed chain (poor) using a Monte Carlo pivot algorithm.