Exploring High-Pressure Transformations in Low-Z (H2, Ne) Hydrates at Low Temperatures
نویسندگان
چکیده
The high pressure structural behavior of H2 and Ne clathrate hydrates with approximate composition H2/Ne·~4H2O featuring cubic structure II (CS-II) was investigated by neutron powder diffraction using the deuterated analogues at ~95 K. CS-II hydrogen hydrate transforms gradually to isocompositional C1 phase (filled ice II) around 1.1 GPa but may be metastably retained up 2.2 GPa. Above 3 a gradual decomposition into C2 (H2·H2O, filled Ic) VIII’ takes place. Upon heating 200 K transition completes instantly whereas appears sluggish also observed 8 At 95 can below 1 yield Ic, respectively, upon complete release pressure. In contrast, neon undergoes pressure-induced amorphization 1.9 GPa, thus following general trend for noble gas hydrates. amorphous crystallizes as mixture previously unreported VIII’.
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ژورنال
عنوان ژورنال: Crystals
سال: 2021
ISSN: ['2073-4352']
DOI: https://doi.org/10.3390/cryst12010009