The structure of chrysotile

Abstract

It has been shown in a previous communication (Whit-taker, 1951) that there exist two varieties of chrysotile, of which the better known form is monoclinic and the other is orthorhombic. Preliminary structure analyses of both these varieties have now been made, based on the hO1 reflexions. The intensity data were obtained from semi-integrating equi-inclination rotation photographs (Whittaker, 1953) taken with crystal reflected CuKa radiation. The multiple-film technique was used, and the photographic densities were measured with a micro-densitometer. Analysis of the intensities of the h00 reflexions confirms the type of structure proposed by Aruja (1943) for clino-chrysotile, and shows that the structure of ortho-chrysotfle is based on the same layer sequence. Some further refinement of both structures has been carried out by trial-and-error methods and by Fourier methods using the h00, h02 and h04 reflexions.