Optical properties of liquid tin between 0.62 and 3.7 eV

The optical constants of liquid tin at 261 °C have been deduced from ellipsometric measurements for photon energies between 0.62 and 3.7 eV. Liquid tin behaves like a nearly-free-electron metal over the measured range. The Drude parameters were derived from the real part of the dielectric constant, giving $\tau =4.90\mathrm{}\times {10}^{-16\mathrm{}}$ sec for the relaxation time and $\frac{m^{*}}{m}=0.98\mathrm{}$ for the ratio of the effective mass to free-electron mass. Comparison is made with previous results for liquid tin and also with data for solid tin.