Electron Energy States inSb2Se3

The transition strenth ${\left(h\nu \right)}^2{\epsilon }_2$, computed by Kramers-Kronig analysis of optical reflectance spectra, is compared with x-ray photoelectron spectra for both single-crystal and amorphous ${\mathrm{Sb}}_2$ ${\mathrm{Se}}_3$. The similarity of the data from x-ray photoelectron spectra for the two modifications suggests that the valence-band structure is essentially the same, whereas differences in the spectral dependence of ${\left(h\nu \right)}^2{\epsilon }_2$ suggest that the conduction-band density of states is lower in the amorphous material, or that the matrix elements for optical transitions are suppressed.