The Crystal Structure of the Dioctahedral Mica 2M2 Determined by High Voltage Electron Diffraction

A. P. Zhoukhlistov, B. B. Zvyagin, S. V. Soboleva and A. F. Fedotov
Academy of Sciences, Moscow, U.S.S.R.

Abstract: The structure of a dioctahedral 2M2 mica was defined by high voltage electron diffraction. The cell parameters are: a = 8·965, b = 5·175, c = 20·31 Å, β = 100° 40′, Z = 4, space group C2/c. Despite the peculiar character of the layer disposition (σ4 σ5 σ4 σ5), the oxygens of the layers are packed according to the cubic law. Consequently, the interlayer cations K have a trigonal prismatic coordination. The angle of tetrahedral twist is 11° 20′. The interatomic distances T-O indicate ordered replacements of Al for Si.

Clays and Clay Minerals; December 1973 v. 21; no. 6; p. 465-470; DOI: 10.1346/CCMN.1973.0210606
© 1973, The Clay Minerals Society
Clay Minerals Society (www.clays.org)