Dehydration rate of the glycine‐MgSO4·5H2O complex and the stability of glycine expelled from the complex by in situ Raman spectroscopy under Mars‐relevant conditions

In this work, we studied the dehydration process of the glycine‐MgSO4·5H2O complex under Mars‐relevant conditions (99% CO2 and 0.6% H2O under ultra violet (UV) irradiation exposure at 7‐mbar pressure and high vacuum conditions: 8 × 10−5 and 5 × 10−5 mbar) by in situ Raman spectroscopy inside a planetary atmosphere and surface chamber (PASC). This work provides quality Raman spectra taken under simulated planetary conditions (to be integrated in a database), as Raman spectroscopy forms part of the current and upcoming NASA and ESA Mars planetary missions. The results demonstrate that Raman spectroscopy can be used to calculate rates of dehydration of the glycine‐MgSO4·5H2O compound to study the chemical stability with respect to photodecomposition (1) of metal‐bound glycine molecules forming the complex and (2) glycine expelled from the complex, both under Mars‐simulated conditions; finally, Raman spectroscopy can also be used to quantify intermolecular interactions in terms of local pressures. Importantly, advanced detection of water molecules as part of a complex with astrobiological interest under planetary conditions plays a crucial role in planetary missions. The evolution of Gly·MgSO4·5H2O, a molecule with planetological interest, is studied at Mars‐relevant conditions during its dehydration and UV irradiation by the in situ Raman spectroscopic. This work provides Raman spectra taken under simulated planetary conditions as Raman spectroscopy forms part in the current and upcoming NASA and ESA Mars planetary missions.