Researchers at the University of Nevada, Las Vegas, compressed water samples beyond 222 gigapascals—replicating conditions closer to those found inside ice giants like Neptune and Uranus—to discover that solid water adopts an unexpected lower-symmetry atomic structure under extreme force, according to a peer-reviewed study published October 15, 2026.
Water behaves in ways that upend standard physics models. When researchers squeeze materials together, the volume shrinks and atoms crowd closer, typically forming more orderly, higher-symmetry arrangements. Water, however, refuses to follow that script.
A new study published in Communications Chemistry reveals that solid water subjected to immense pressure reorganizes into a lower-symmetry version of itself. The peer-reviewed paper, titled Evidence for symmetry-reduction in solid H2O above 222 GPa
, documents how water alters its underlying chemistry and structural appearance when forced far beyond familiar terrestrial conditions.
Diamond Anvil Cells and 35 Million PSI Inside the Nevada Extreme Conditions Lab
The experiment required pushing water into states that defy ordinary laboratory environments. Led by UNLV physicist Ashkan Salamat, the research team utilized spectroscopy to examine samples squeezed between two diamonds—recognized as the hardest known material—to generate extraordinary force. X-rays then mapped the structural arrangement of the compressed atoms.
The team applied forces exceeding 222 gigapascals, creating conditions equivalent to approximately 35 million pounds per square inch. For comparison, a standard car tire operates at roughly 30 PSI. That staggering pressure transformed the solid water’s atomic symmetry, proving that squeezing the molecule drives unexpected structural shifts rather than standard uniform ordering.
Laboratory Extremes Mirror Ice Giant Interiors
These laboratory extremes mirror the hidden interiors of distant planets. Neptune and Uranus are classified as ice giants, functioning essentially as massive spheres composed of molten, metallic-like water alongside ammonia and methane. Direct exploration of their deep crusts and atmospheres remains impossible due to distance, leaving planetary scientists to rely on data gathered by missions such as the Voyager program.
While planetary flybys provide estimates of interior temperatures and pressures, laboratory experiments bridge the gap by replicating the chemical behavior likely occurring deep within those worlds. Researchers note that if the extreme pressure were eventually released, the cosmic water would likely rearrange itself back into a familiar structure recognizable on Earth.
We can’t enter the crust or atmospheres of these planets because of distance, but we have data from things like the Voyager program. We have an idea of their compositions, and interior pressure and temperatures. And in labs like mine, we can mimic the chemistry and experiment with what could be occurring inside these planets.
US Institutions Collaborate on Planetary Simulation Study
The published findings stem from a collaborative scientific effort uniting institutions across the United States. Researchers from the University of California, Berkeley, and Argonne National Laboratory joined UNLV faculty to complete the analysis.
Alongside research lead Ashkan Salamat, the study’s co-authors include Zachary Grande, Victor Robinson, Dean Smith, Jesse Smith, Oliver Tschauner, and Burkhard Militzer. Their work highlights how laboratory simulations provide vital empirical data for broader planetary models, pushing past assumptions about how matter behaves across the solar system.
Understanding the mechanisms of our solar system and our observable universe is critical for the endeavor of human knowledge. When we eventually get to these worlds, what are we going to see? We’re really the initial pioneers in trying to answer these questions in the laboratory.