Oxysulfides, lanthanide

Table 9. Effect of pressure on the crystal field parameters (cm ) for Eu + in several lanthanide oxysulfide systems. S (cm ) is an average crystal field strength parameter (see text). P denotes pressure in kbar and represents the maximmn pressine achieved in each stndy. The...

I. Valsamakis, M. F. Stephanopoulos, Sulfur-tolerant lanthanide oxysulfide catalysts for the high-temperature water-gas shift reaction, Appl. Catal. B Environ. 106 (2011) 255-263. 

Gschneidner et al. (1973) used this technique along with some limited experimental data to predict the free energies of formation at 1100 K, and heat of formation at 298 K of the rare earth oxysulfides. Recently, Akila et al. (1987) measured the free energies of formation of eleven lanthanide oxysulfides and they noted that there was... 

The oxysulfides I.n202S (Ln lanthanide) (see also Sect. 7.3) are also used as X-ray phosphors. The phosphor crystallizes in nearly perfect polyhedra. Figure 8.10 gives an example for Gd202S Tb. ... 

Thermal degradation of lanthanide sulfites is comphcated, particularly in inert and reducing atmospheres. In a reducing environment oxysulfides are formed, offering a convenient route to oxysulfide phosphors. The Ce(III) sulfite-sulfate compounds appear to have an interesting apphcation in thermochemical cycles. 

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