Optical constants of Sc, V, Cr, Co, Ni, Nb, Mo, Rh, Pd, Hf, W, Re, Os, Ir, Pt, Au, and ZrO ₂ in the extreme ultraviolet range

Transition metal coatings are of fundamental value for extreme ultraviolet (EUV) optics. Often, the reported optical constants for transition metals in the EUV range exhibit inconsistencies across different publications. Therefore, additional studies to determine optical constants in the EUV range for transition metals are highly relevant to further develop optical components. In our work, the optical constants of scandium, vanadium, chromium, cobalt, nickel, niobium, molybdenum, rhodium, palladium, hafnium, tungsten, rhenium, osmium, iridium, platinum, gold, and zirconium dioxide are determined in parts of the EUV spectral range. The optical constants were determined from angle-dependent reflectance measurements collected using monochromatized synchrotron radiation. We also test capping solutions for thin coatings of scandium, vanadium, cobalt, niobium, molybdenum, hafnium, tungsten, and rhenium. All of our results are presented in comparison with literature data. For many cases, our results present either significant scale deviation or previously unresolved fine-structure in the widely used optical data compilations.