A method is described for the determination of the amorphous content of polythene samples, based on a microphotometric comparison of the intensities of the amorphous band and the two strongest crystalline lines on X-ray powder photographs obtained from the samples in sheet form. Corrections for two types of orientation are described. The results indicate that amorphous contents at ordinary temperatures may vary from below 10% to above 50%, normal samples having an amorphous content of about 25%. The more amorphous samples have lower densities; the quantitative relation between density and degree of crystallinity is discussed.

The title compound, C₂₃H₂₃NO₂SSi, at 100 K adopts a boat conformation which brings the C—H bond of an axial phenyl substituent into proximity [CN = 3.376 (1) Å] with the aziridine lone pair. The factors which favour this conformation for bi­cyclo­[3.1.0]­hexane systems are considered.