Compacted Magnesium Fluoride: Preparation, Characterization, and Optics

Abstract

The electronic structure and the effect of defects on the optical properties of magnesium fluoride are studied by X-ray photoelectron spectroscopy (XPES). A deviation from fluorine stoichiometry in MgF_2−x is shown to give rise to a long-wavelength shift of the absorption edge. The color of a defective magnesium fluoride caused by the absorption in the range 215–300 nm, low mechanical strength, and optical instability are related to the defectiveness of the fluorine sublattice. A way to reduce the defectiveness is to use specific synthetic procedures and dope the material to be vaporized with a fluorine donor.