Figure 1

Principal peak in neutron diffrac­tion patterns from HDA at 0 and 2.2 GPa (main figure). Inset (a) compares the complete 0 GPa data (upper plot) with published ambient pressure $S\left(Q\right)$ data [11] plotted as a function of $Q=2\pi /d$. Inset (b) shows the phase diagram of water, including the domain of existence of HDA. The broad line shows schematically the recrystallization temperature and dashed lines are extrapolated phase boundaries. The arrows show the $P\mathrm{\text{−}}T$ paths followed in the recrystallization experiments mentioned in the text.Reuse & Permissions

Figure 2

Site-site radial distribution functions $g_{\alpha \beta }\left(r\right)$ of HDA at 0, 0.7, and 2.2 GPa, and $g_{\mathrm{O}\mathrm{O}}\left(r\right)$ data for water at 0 and 0.4 GPa at 268 K [8]. The first peaks in $g_{\mathrm{O}\mathrm{D}}\left(r\right)$ (at $\sim 1.8Å$) and $g_{\mathrm{D}\mathrm{D}}\left(r\right)$ (at $\sim 2.2Å$) are, respectively, the $\mathrm{D}\mathrm{\cdots }\mathrm{O}$ hydrogen bond length and the intermolecular D-D distance. The strong intramolecular contributions to $g_{\mathrm{O}\mathrm{D}}\left(r\right)$ and $g_{\mathrm{D}\mathrm{D}}\left(r\right)$ at 1.0 and 1.5 Å have been subtracted for clarity.Reuse & Permissions

Figure 3

The main plots show the spatial distribution functions (SDFs) of the oxygen atoms. The upper plots were obtained from data collected at 0 GPa and show (left) the density in the range 2.0–3.1 Å (the first coordination shell) and (right) from 2.0–4.8 Å (the first and second coordination shells). The middle plots, from data collected at 0.7 GPa, show (left) the density in the range 2.0–3.1 Å and (right) from 2.0–4.6 Å. The lower plots, from data collected at 2.2 GPa, show (left) the density in the range 2.0–3.0 Å and (right) from 2.0–4.3 Å. The insets show the distribution of dipole orientations for water molecules at the arrowed positions in the SDFs. The levels of all isosurfaces have been set to enclose 40% of the molecules within the specified ranges.Reuse & Permissions