Investigation of lanthanide interaction with arsenic (3) sulfide

Rare earth interaction with As2S3 was studied by differential-thermal X-ray diffraction and chemical methods. It is shown that this interaction proceeds in a complicated way and depends on experiment conditions. Formation of sulfoarsenides and rare earth arsenides takes place at temperatures above 1200 deg K. Rare earth sulfides of various compositions form at temperatures below 1100 K and at certain component ratios. Formation of rare earth sulfides passes through two stages: at first a metal reacts with sulfur vapors, formed in result of thermal decomposition of arsenic sulfide, and then exchange reactions proceed. Dependence of thermal characteristics of reactions and interaction products, as well as of sulfide crystal structure on rare earth atomic number is discussed