The previously unknown crystal structure of the polymer/salt complex poly(ethylene oxide):${\mathrm{NaSO}}_3$${\mathrm{CF}}_3$ was solved from a powder-diffraction pattern collected on a laboratory x-ray diffractometer. The solution was performed starting from a random arrangement of constituent molecular fragments in the unit cell using a full-profile-fitting technique and a simulated-annealing method for finding the global minimum of the figure-of-merit function. Unlike the only other structure solution using this approach, the procedure was successful only when the highest degree of flexibility was applied to stereochemically constrained species.

DOI:https://doi.org/10.1103/PhysRevB.55.12011