Synthesis and Crystal Chemistry of Sulfides and Tellurides with the Th3P4 Structure,
Abstract
Chalcogenides, with the Th3P4 structure were identified as potential IR window materials. A crystal chemical evaluation showed that this chalcogenid structure alone is cubic with all cations in 8-fold coordination. Compounds with the formula MLn2S4 (where M=Ca, Sr, Ba, Eu(2+), Pb, and Cd and Ln = La, Ce, Pr, Nd, Sm and Gd) were synthesized by reaction of the oxides or carbonates in flowing H2S at temperatures of 1000-1200C. The materials were fine-grained powders, refractory (melting point about 1800C), are chemically stable in atmospheric ambient. Band gaps were on the order of 2.5 to 3.0 electron volts when no mixed valence ions were present. Attempts to grow large single crystals by flux and CVD methods were unsuccessful.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 30, 1974
- Accession Number
- ADA008490
Entities
People
- Paul L. Provenzano
- William B. White
Organizations
- Pennsylvania State University