Accession Number : AD0668722

Title :   RELATION OF MECHANICAL PROPERTIES TO THE STRUCTURE OF IONIC SOLIDS.

Descriptive Note : Quarterly rept. no. 7, 1 Dec 67-28 Feb 68,

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK MATERIALS RESEARCH LAB

Personal Author(s) : Vedam,K. ; Newnham,R. E.

Report Date : 20 MAR 1968

Pagination or Media Count : 41

Abstract : Bending experiments on micas confirm the existence of nonlinear stress-strain relationship in these ionic crystals. The crystal structure of synthetic 1M-BaLiMg2AlSi3O10F2 mica was refined by least squares and Fourier methods to an R-factor of 7.1% in space group C 2/m. There is no ordering of lithium and magnesium in the two octahedral sites. The structures of fluorophlogopite and barium mica were compared and the differences analyzed in terms of local charge imbalance, the valency of the interlayer cation and decreased cation-cation repulsion in the octahedral sheet. The physical properties of these micas and others are analyzed in terms of their structural features. (Author)

Descriptors :   (*MICA, MECHANICAL PROPERTIES), (*SILICATES, *CRYSTAL STRUCTURE), BENDING, STRESSES, STRAIN(MECHANICS), NONLINEAR SYSTEMS, BARIUM COMPOUNDS, LITHIUM COMPOUNDS, MAGNESIUM COMPOUNDS, ALUMINUM COMPOUNDS, FLUORIDES, CRYSTAL LATTICES, VALENCE, MOLECULAR ASSOCIATION, CERAMIC MATERIALS, SIMULATION

Subject Categories : Ceramics, Refractories and Glass
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE