Structural study of chiral camphorsulfonic acid doped polyaniline

Chiral camphorsulfonic acid [R-(-)-CSA] doped polyaniline (PANI) films have been studied using X-ray diffraction in combination with structure factor calculations. Scattering studies of dedoped films, which exhibit chiral act ivity, have also been performed. All samples formed partially crystalline f ilms and displayed significant molecular anisotropy in the crystal unit cel l with respect to film orientation. The crystalline features are interprete d using a lamellar molecular model in which parallel stacks of the PANI mai n chains alternate with layers of the CSA dopant. This organization could, in part, explain the high conductivities often recorded in CSA-doped films. No obvious features within crystalline regions of the doped or dedoped fil ms were observed which correlate with the chiral recognition seen in dedope d films.