Monochalcogenides of the Rare-Earth Elements and Their Alloys Having Semiconductor Conductivity

Optical investigation of ytterbium monochalcogenides

“…1. They a r e rather similar to the spectra of europium and samarium monochalcogenide powders (1,2) All these spectra a r e characterized by the presence of absorption bands designated by us as a , b , c , and d and by an increase of the absorption coefficient in the region of higher energies. The spectral locations of absorption maxima a r e represented in Table 1.…”

“…The positions of the absorption edges of europium (1) and samarium (2) monochalcogenides determined by the diffusive reflection spectra a r e due to transitions between YbSe and YbTe, respectively, are also attributed by the authors of (7) to 4fl -transitions.…”