Schematic diagram (not to scale) of the experimental apparatus used for benzene ice nucleation and growth studies (adapted from D. Dubois et al. 2021). Pressure was measured with a capacitance manometer (P1) and an ion gauge (P2). The inset shows a top view of the cooled sample holder with the positions of the three K-type thermocouple gauges (red dots) used for temperature measurements. The ice sample formed on either or both sides of the silicon substrate/tholin sample (gray), which was in the path of the IR beam of the Thermo Fisher iS50. IR transmission spectra were collected with a liquid N₂-cooled MCT/A detector.