Accession Number : AD0776322

Title :   Transition Metal Ions and Heterogeneous Nucleation in Glass.

Descriptive Note : Annual rept.,


Personal Author(s) : Aitken,John ; Moon,Deug ; MacCrone,Robert K. ; Cieloszyk,Gary

Report Date : JAN 1974

Pagination or Media Count : 79

Abstract : Magnetization measurements on x Fe2O3 (1-x) (BaO.4B2O3) glasses have been made over the temperature range from 50 mK to 300K for 0 < x < 0.10. Electron paramagnetic resonance measurements were also made on the same specimens at the temperatures 300 and 77K. These structure sensitive measurements reveal that the majority of the iron ions exist in pairs (diads) and in groups of three, (triads). The isolated Fe(+3) concentration was obtained from the epr g=4.28 resonance. The existence of the triads was inferred from their magnetic susceptibility. This susceptibility was obtained by subtracting the theoretical magnetization of the isolated ions from the total measured value. On the assumption that the triads order at liquid helium temperatures with a resultant moment equal to one of the members, the concentration of isolated Fe(+3) ions as a function of total Fe2O3 content was independently determined, and found to be in quantitative agreement with the epr measurements. (Modified author abstract)

Descriptors :   *Glass, *Amorphous materials, *Iron, *Crystal structure, Transition metals, Electron paramagnetic resonance, Borates, Nucleation, Ferromagnetism

Subject Categories : Ceramics, Refractories and Glass

Distribution Statement : APPROVED FOR PUBLIC RELEASE