Scientists squeezed a water droplets between two diamonds and blasted it to star-like temperatures with one of the world's most powerful lasers. A new phase of water was created.
The "strange, black" water is similar to those at the center of Earth and could help researchers investigate the secrets buried inside the cores of other worlds.
This weird ice was created using shock waves. This is the first time scientists have created stable superionic ice that lasts long enough to be studied. The findings were published in the journal Nature Physics.
No two are alike.
"Everyone thought this phase wouldn't appear until you are at much higher pressures than where we first find it," study co-author Vitali Prakapenka, a beamline scientist at the Advanced Photon Source, said.
Water's most common phases are liquid, vapor and ice, but water can also be settled into other arrangements that represent different phases. Scientists have identified the different ways in which hydrogen and oxygen atoms can stack under different temperatures and pressures.
Ice VI and ice VII have molecule that arrange themselves into rectangular cubes. Ice XI flips sides if it's placed inside an electric field, and ice XIX is brittle and only has its hydrogen atoms form a regular pattern.
The superhot and highly pressurized superionic ice is the 18th phase of ice to be discovered, and it's one of the strangest yet. It's because the hydrogen atoms give up their electrons and become ion atoms, which are free to flow through the ice as if they were a fluid.
"Imagine a cube with a lattice of oxygen atoms at the corners connected by hydrogen," Prakapenka said. The lattice expands when it becomes a new superionic phase, allowing hydrogen atoms to migrate around while oxygen atoms stay in their positions. It's like a lattice of oxygen and hydrogen floating in the water.
The black appearance of the ice is caused by the swimming hydrogen atoms blocking light from passing through it.
The first evidence of superionic ice was found by researchers at the Lawrence Livermore National Laboratory in California, Live Science previously reported. Researchers achieved the temperatures and pressures required for superionic ice to appear by using a high-pressure shock wave to blast a water droplet.
Prakapenka and his colleagues needed to create a more stable form of ice to take more detailed measurements. They squeezed the water with a diamond anvil and then blasted it with a laser. The diamond's hard surface allowed the anvil to pressurize the droplet to 3.5 million times Earth's atmospheric pressure and the laser to heat it to temperatures hotter than the surface of the sun. X-ray beams were launched at the droplet with a device called a synchrotron. The researchers were able to identify the structure of the ice by measuring the X-rays that were scattered by the atoms inside.
This method gave the researchers a longer time frame to observe their ice than the shock-wave experiment had. The extra time gave them the ability to chart the different phases of the water droplets.
Scientists can use further study to better understand the ice's properties and the conditions under which different ice phases occur. The researchers wonder if the superionic ices are buried in the cores of planets such as Neptune and Uranus, or trapped inside the frozen seas of Jupiter's moon Europa. The ices could play a role in the creation of the magnetospheres that surround these worlds or alien worlds beyond our solar system. Knowing how and where superionic ice forms could become an extremely useful guide for scientists searching for alien life in the magnetospheres is important.
The new ice has many more properties that are crucial for predicting where the weird ice might form elsewhere.
"It's a new state of matter, so it acts as a new material, and it may be different from what we thought," Prakapenka said.
Live Science published the original article.
