Accession Number : AD0635653

Title :   COMPOUNDS WITH DEFECT STRUCTURES.

Descriptive Note : Progress rept. no. 5, 1 Oct 65-31 Mar 66.

Corporate Author : POLYTECHNIC INST OF BROOKLYN N Y

Personal Author(s) : Banks, E.

Report Date : 31 MAR 1966

Pagination or Media Count : 12

Abstract : Crystals in the system Mn2-xFex03 (0<x<1) and Mn1.8A10.203 were grown by anodic electrolysis from tungstate melts. Their reciprocal susceptibility-temperature curves show apparent antiferromagnetic behavior and large negative Weiss constants. A number of fluxes were tried in the effort to obtain large crystals of fluoride-substituted copper ferrite, with the production of small crystals of spinel structure, some of which are tetragonal, and others cubic. Least-squares refinement of the structure of the spodiosite Ca1P04C1 to an R value of 0.043 has led to atomic positions accurate to plus or minus 0.001A for the heavy atoms and plus or minus 0.002A for the oxygens. Further studies of the absorption spectrum of Yb3+ in CdF2 were made for the purpose of understanding the appearance of an absorption peak at 977 nm, which disappears as interstitial fluoride ions are replaced by Na(+) as the charge compensator. This peak does not appear in CaF2-Yb(3+), but is present in CdF2 and PbF2.

Descriptors :   (*CHEMICAL COMPOUNDS, SOLID STATE PHYSICS), (*MANGANESE COMPOUNDS, MAGNETIC PROPERTIES), (*FERRITES, CRYSTAL GROWTH), (*PHOSPHATES, ATOMIC STRUCTURE), (*YTTERBIUM, ABSORPTION SPECTRA), MOSSBAUER EFFECT, CRYSTAL STRUCTURE, ALUMINATES, SOLID SOLUTIONS, FLUORIDES, SUBSTITUTION REACTIONS, COPPER COMPOUNDS, SPINEL, CALCIUM COMPOUNDS, CHLORIDES, CADMIUM COMPOUNDS, CRYSTAL DEFECTS, CERAMIC MATERIALS

Subject Categories : Crystallography
      Atomic and Molecular Physics and Spectroscopy
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE