- 1National Institute for Astrophysics (INAF) , Osservatorio Astronomico di Palermo, Palermo, Italy
- 2Department of Physics, National Central University, Zhongli Dist., Taoyuan City, Taiwan (asperchen@phy.ncu.edu.tw)
Icy grain mantles act as crucial reservoirs for volatile elements and chemical diversity. A major open question regarding their morphology is whether these ices are uniformly mixed or segregated into distinct layers.
This study investigates the chemical and structural evolution of a ternary H₂O:NH₃:CO mixture through laboratory experiments simulating layered and homogeneously mixed ices. We produced mixed and stratified ices using classical isothermal deposition and cooling ramps from 200 K to 10 K, both with and without X-ray irradiation. Depending on the parameters used, the ice evolves into diverse structural, chemical, and thickness configurations. Furthermore, we demonstrate that the CO stretching mode serves as a sensitive probe, reflecting the distinct chemical and structural environments within the ice.
How to cite: Ciaravella, A., Jimenez-Escober, A., Piazzese, F., Cecchi Pestellini, C., and Chen, Y.-J.: Uniformly mixed vs segregated layers: the evolution of H₂O:NH₃:CO ices, Europlanet Science Congress 2026, The Hague, The Netherlands, 7–11 Sep 2026, EPSC2026-860, https://doi.org/10.5194/epsc2026-860, 2026.
