Molecular conformation of linear polyphosphonitrile chloride

The interpretation of the x‐ray fiber photograph of stretched linear polyphosphonitrile chloride was carried out by means of Fourier transform methods with the aim of establishing the chain conformation without considering the mode of packing in the crystal lattice. The results of such an analysis lead to the conclusion that the radial distribution of the intensities on the layer lines is consistent with a twofold helical conformation characterized by values of 156° and 14° for the angles of rotation around the PN and NP bonds, the cis ‐planar conformation corresponding to angles of rotation of π and 0°.