Structure of Kaolinite

Abstract

THE generally accepted structure of kaolinite was elucidated by Gruner¹ from X-ray powder photographs, and Hendricks² afterwards gave confirmatory data obtained by electron diffraction. They find a monoclinic structure with cell dimensions a = 5·14 A., b = 8·90 A., c = 14·51 A., β = 101° 30', consisting of sheets of Si-O tetrahedra and Al-OH octahedra arranged parallel to the basal plane (001), there being two sheets in each unit cell. Gruner based his structure on measurements of some forty reflexions. Other workers³ have since published lists of kaolinite reflexions aiming at higher accuracy in the spacing measurements rather than increasing the number of recorded reflexions. Apart from the work of Hendricks, we know of no further attempt to study the structure of the mineral since the publication of Gruner's analysis.