Hydrogen bonding, thermal expansion, and phase transition of cranswickite (MgSO4 · 4H2O)

Cranswickite and starkeyite are two polymorphs of MgSO₄·4H₂O and are candidate minerals in the hydrated sulfate deposits on Mars. Using neutron powder diffraction, we studied cranswickite’s structure, hydrogen bonding and thermal expansion, and its irreversible transformation to starkeyite. We used dispersion-corrected density functional theory (PBE+TS and r2SCAN+D4) to assess how stable the two polymorphs are relative to each other at various pressures . This dataset contains the input and output files of these calculations. This dataset accompanies a manuscript submission to Acta Crystallographica Section B. The entry will be updated upon acceptance of the paper.