X-ray Study of the Interlayer Region of a Barium—Vermiculite

M. I. Telleria, P. G. Slade and E. W. Radoslovich
C.S.I.R.O. Division of Soils, Glen Osmond, South Australia 5061

Abstract: An X-ray diffraction analysis of a barium-vermiculite shows it to have a triclinic unit cell with the following dimensions a = 5.33, b = 9.26, c = 12.47 Å, α = 100.75° β = 93.5° and γ = 90°. The proposed structure, adjusted in space group C1, has the exchangeable cations approximately over the ditrigonal holes of the silicate surface and on either side of a hexagonal network of water molecules extending over the middle of the interlamellar region. The interlayer material imposes a relative displacement of ±b/4 on adjacent silicate sheets. The importance of these displacements, not previously found in layer silicates, is emphasized.

Clays and Clay Minerals; May 1977 v. 25; no. 2; p. 119-125; DOI: 10.1346/CCMN.1977.0250208
© 1977, The Clay Minerals Society
Clay Minerals Society (www.clays.org)