Ammonia Mono Hydrate IV: An Attempted Structure Solution

Crystals

Bernhard Massani¹  Andreas Hermann¹  John S. Loveday¹  Ciprian G. Pruteanu¹  Lewis J. Conway¹  Victor N. Robinson¹ 

[1] SUPA, Centre for Science at Extreme Conditions, School of Physics and Astronomy, The University of Edinburgh, Edinburgh EH9 3FD, UK;

关键词: ammonia hydrate;    high pressure;    neutron diffraction;    density functional theory;   

DOI  :  10.3390/cryst12020135

来源: DOAJ

【 摘 要 】

The mixed homonuclear and heteronuclear hydrogen bonds in ammonia hydrates have been of interest for several decades. In this manuscript, a neutron powder diffraction study is presented to investigate the structure of ammonia monohydrate IV at 170 K at an elevated pressure of 3–5 GPa. The most plausible structure that accounts for all features in the experimental pattern was found in the P$2_1/c$ space group and has the lattice parameters $a=5.487\left(3\right)$ Å, $b=19.068\left(4\right)$ Å, $c=5.989\left(3\right)$ Å, and $\beta =99.537\left(16\right)$ deg. While the data quality limits discussion to a proton-ordered structure, the structure presented here sheds light on an important part of the ammonia–water phase diagram.

【 授权许可】

Unknown