Synthesis and Crystal Chemistry of Oxysulfides with the Garnet Structure,

Abstract

In a search for new ternary materials with potential suitability for 10.6 micrometer window applications, the sulfur analogs of the garnet structure were investigated. Pure sulfur end-member garnets cannot be synthesized under ambient pressures. A series of oxysulfide garnets with sulfur to oxygen ratios of 7.5/4.5 were discovered. These have the general formula (Ln3(VIII)Me2(VI)Me3(IV)O4.5S7.5) where Ln is any rare earth except La(3+) and Me is a variety of 2+, 3+, and 4+ transition metal ions plus Mg(2+) and Ga(3+). A total of more than 40 compounds have been synthesized and are characterized by x-ray diffraction data. IR spectra of selected garnets indicate that the highest frequency transverse optic mode lies in the range of 470/cm. Complex spectra from two garnets indicate the possibility of anion ordering. (Modified author abstract)

Document Details

Document Type
Technical Report
Publication Date
Aug 30, 1973
Accession Number
AD0774641

Entities

People

  • R. R. Neurgaonkar
  • William B. White

Organizations

  • Pennsylvania State University

Tags

DTIC Thesaurus Topics

  • Absorbers (Materials)
  • Abstracts
  • Advanced Materials
  • Chemistry
  • Crystal Chemistry
  • Diffraction
  • Engineered Materials
  • Frequency
  • Materials
  • Metals
  • Micrometers
  • Spectra
  • Transition Metals
  • Transitions
  • X Rays
  • X-Ray Diffraction

Readers

  • Materials Science and Engineering.