Vacuum UV high-performance spectrophotometric setup for use in the 105–200-nm wavelength range

A complete vacuum UV spectrophotometric device, including the source and a computerized data acquisition system, for both reflectance and transmittance measurements in the 105-200-nm wavelength range is described. The apparatus is suitable for various experimental situations such as measurements in the -200 to +100 degrees C temperature range for gases, liquids, and solids (for gases and liquids within the 0-150 bar pressure range). Drift of 0.07% per day for ambient temperature measurements and absolute reflectance as low as 0.05% are reported, illustrating the high performance reached. The setup is particularly well suited for long cycles of low temperature, high pressure experiments.