The Press Stories
Ice XIX is the second hydrogen-partially ordered phase Ice VI, A previously known ice form at pressures around 1 GPa and temperatures between 130 and 355 K.
Description showing the relationship between ice VI and XIX unit cells, differences in their C-axes and their variant shapes, color index red for ice XIX and blue for ice VI. Image credit: University of Innsbrook.
“Different types of ice have different shapes and very different properties depending on the pressure and temperature,” he said Dr. Thomas Lording From the Institute of Physical Chemistry at the University of Innsbruck and his colleagues.
“18 crystalline icebergs, including conventional ice I, have been known so far that differ in the arrangement of their atoms.”
“When the ice cools down strongly, if the test is performed properly, the hydrogen atoms can regulate themselves in addition to the oxygen atoms.”
“Below 73 K, this leads to what is called ice XI, in which all water molecules are sequenced in a certain way. Such ordered ice patterns differ from irregular parent forms, especially in their electrical properties.”
In 2009, a team of researchers in Europe Made by Hydrogen-ordered variant of ice VI, which entered textbooks Snow XV.
By changing the production process, Dr. Boarding and colleagues recently won In creating the second sorted ice VI.
To do this, they significantly reduced the cooling process and increased the pressure to about 2 GPa.
This helped them to organize the hydrogen atoms in a second way in oxygen lattes and to create a new form of ice called ice XIX.
“We then found clear evidence that this was a newly ordered variant, but we were unable to clarify the crystal structure,” Dr. Lording said.
Uses From the site Calorimetry and high-resolution neutron powder difference, scientists studied the crystal structure of ice XIX.
“In general practice, the availability of the crystal structure allows a Roman numeral to be assigned to this ice phase,” they said.
“Following the recent discovery of the supersonic phase Snow XVIII Appearing at ultrahigh-pressure, we add ice XIX to the ice phase diagram in the versatile intermediate pressure range between 0.5 and 2.0 GPA, of which 13 ice polymorphs are now known. ”
“Ice XIX represents a phase in which the same oxygen atomic topology is shared with its parents, the irregular ice VI, and its siblings, somewhat antiferoelectrically ordered ice XV.”
“As the ice heats up XIX it first turns to ice XV above 107 K and then ice VI at 128 K.”
Separate team of physicists, headed Dr. Rio Yemen From the University of Tokyo, confirmed the results of an experiment under different stress conditions.
The findings are found in two documents Magazine Nature Communications.
_____
D.M. Kasar And others. 2021. The structural nature of ice XIX as the second polymorph associated with ice VI. Not Common 12, 1128; doi: 10.1038 / s41467-021-21161-z
R. Yamane And others. 2021. Test evidence for the existence of a partially ordered phase of ice VI. Not Common 12, 1129; doi: 10.1038 / s41467-021-21351-9
