Measurement of spectral emissivity and constant pressure heat capacity of liquid platinum with an electrostatic levitator

Spectral emissivity and constant heat capacity of molten platinum at its melting temperature were measured. A sample was levitated in an electrostatic levitator and the radiation intensity from the molten sample was measured by spectrometers over a wide wavelength range. The spectrometers were calibrated with a blackbody radiation furnace and the spectral hemispherical emissivity was obtained. The obtained emissivity showed a negative wavelength dependence, which can be explained by Drude model. The total hemispherical emissivity of platinum at the melting temperature calculated by integrating the spectral hemispherical emissivity was found to be 0.25. Also, the constant pressure heat capacity was calculated to be 38.8 J·mol⁻¹·K⁻¹.