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The optical properties of the semiconducting compounds (Me = Ti, V, Cr, Mn, Fe, Co, and Ni) crystallizing in the zinc-blende structure have been investigated. Reflectivity spectra of these materials have been taken at room and liquid nitrogen temperatures. The measurements have been performed in the 4 - 25 eV energy range using synchrotron radiation from the ADONE storage ring in Frascati. Comparisons between the reflectivity spectra of the ternary systems and those of the host crystal ZnSe have been made, and models explaining the influence of the transition metal ions on the electronic structure of the host crystal ZnSe have been discussed.

In this paper we present a comprehensive study of the tetrahedral semiconductor ZnSe crystallizing in the zincblende structure. The electronic structure of ZnSe has been determined first using the ab initio self-consistent linear muffin-tin orbital method with a local-density form of the exchange-correlation functional. Then it has been adjusted to reproduce the experimental energy positions of the Zn 3d bands and of the optical gap. The adjusted electronic structure, densities of states and interband optical properties are presented and compared with previous calculations. Good agreement with experimental photoemission and bremsstrahlung isochromat measurements was found after including an energy-dependent lifetime broadening. We measured the reflectivity of ZnSe with high resolution from 4 to 30 eV and the high-energy region of the spectra has been interpreted on the basis of the present calculation.

The design of a beamline, covering the energy range from 5 to 200 eV, based on a double incidence spherical gratings monochromator designed for ELETTRA bending magnet radiation is described. The monochromator consists of two interchangeable sets of gratings working one at normal incidence and the other at grazing incidence, to cover the entire spectral interval. The photon energy range of interest is covered with five gratings (two at normal and three at grazing incidence) achieving a resolving power of the order of 10000 and a photon flux approximately 1012 (photons/s/0.1% bandwidth/mm2) at the sample position.