Méthode d'analyse du profil de bande produite par des feuillets diffractants ayant une forme anisométrique

Solids characterized by lamellar structure are often made from ribbon or lath-shaped sheets. Such a morphology has been observed in phyllosilicates (hectorite or nontronite, for example) and in carbon fibres. This contribution aims to show that elongated planar sheets can be detected from the profile of the X-ray diffraction bands yielded by the powdered solid. The numerical technique originally developed by Brindley & Méring [Acta Cryst. (1951). 4, 441-447] for isometric layers, has been extended to ribbon or lath-shaped elementary layers. An example of application is given when the sheet is a carbon layer.