Optical Properties of Platinum

The optical functions ${\epsilon }_1$, ${\epsilon }_2$, $\alpha$, and $-\mathrm{Im}\left(\frac{1}{\epsilon }\right)$ have been deduced from reflectance data on electron-gun-evaporated Pt samples. They were obtained by two different methods: (1) the Kramers-Kroning analysis of the normal-incidence reflectance data, and (2) the analysis of reflectance at two different incident angles. The absorption coefficient $\alpha$ shows small peaks at $h\nu =0.4, 7.7, \mathrm{and} 10.5$ eV, and a broad peak centered about 4 eV. The imaginary part of the dielectric function, ${\epsilon }_2$, has structure at $h\nu =6.5\mathrm{}$ and about 11 eV.