Measurements of the optical constants of mercury and mercury-indium amalgams in the spectral region 4000 to 17 000 cm−1

Abstract

The optical constants of liquid mercury have been measured by a reflection method. in the infra-red spectral region 4000 to 17 000 cm⁻¹. The apparatus used has two quartz Roohon prisms, a quartz prism spectrometer, and a lead sulphide photocell. The reflecting surface was a free surface of mercury, which could be enclosed in a hydrogen filled tank. The measured values do not agree with the predictions of the Drude free electron theory. The dielectric constant has a minimum at a wave number ∼ 9 × 10² cm⁻¹. The temperature variation of the optical constants of mercury has been investigated between 20° and 230°c. Measurements have been made of the optical constants of mercury-indium amalgams, between 0 and 33 atm % indium.