YbSe Terminal Solid Solutions

While the sesquiselenides of La to Sm are insoluble in YbSe, the systems with M = Y, Gd to 

Lu form NaCl type solid solutions with a vast range of homogeneity. A cubic superstructure with doubled a is formed from low M2Se3 concentrations not easily defined. This changes in a later stage into the CaH02Se4 lattice by sheer rhombohedral distortion, Souleau et al. [1]. 

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