"Hitler's Acid" might lie at the heart of gas giant planets and their moons

Russian chemists have discovered that some exotic compounds may be formed in high pressure environments like those found inside Uranus, Neptune and other gas giant planets and their moons. The finding could have implications for industry, and for our understanding of the larger planets and their satellites.

In the research, which has been published in Scientific Reports, a team led by Professor Artem R. Oganov from the Moscow Institute of Physics and Technology (MIPT) used a powerful algorithm called USPEX (Universal Structure Predictor: Evolutionary Xtallography) that can predict crystal structure and compound formation.

USPEX has been used in recent years to reveal new substances that are thought to be impossible in classical chemistry but that could be stable at high pressures like those found in the interiors of other planets.

Oganov and co-author Gabriele Saleh from MIPT used the algorithm to study the familiar carbon-hydrogen-oxygen system found in gas giant planets.

"This is an extremely important system because all organic chemistry 'rests on' these three elements, and until now it had not been entirely clear how they behave under extreme pressures and temperatures," Oganov explained. "In addition, they play an essential role in the chemistry of the giant planets."

When the researchers turned the pressure up to around 10,000 atmospheres in the algorithm, they found that carbonic acid becomes stable, which they say is strange since it is quite unstable under normal conditions.

Organov tells New Atlas this could have implications for our understanding of what is going on inside gas giants and their satellites.

"On icy satellites such as Europa, scientists previously believed the silicate core to be in direct contact with a water-rich "ocean" (believed to contain large amounts of CO2 too), and a chemical reaction was expected to occur between the core and the ocean," he explained. "However, our results show that instead of being in direct contact with water, the rocky core will be covered by a layer of solid carbonic acid, preventing any reaction between the core and water of the "ocean."

That lack of chemical reactions in Europa's hidden ocean could be bad news for its prospects of supporting life. The moon of Jupiter is thought to be one of the more promising places to find some sort of off-Earth critters swimming around; NASA is already planning a mission for a closer look.

When the pressure rises further, carbonic acid can convert into a polymer and at one point, it's possible for an exothermic reaction between it and water to occur and create orthocarbonic acid. This compound is extremely unstable and scientists have been unable to produce it in labs. It's also known as "Hitler's Acid," because its molecular structure resembles the shape of a swastika.

"Another implication is that inside giant planets such as Uranus and Neptune, there will be significant amounts of orthocarbonic acid ... (and) carbonic acid in the liquid and probably also in the solid form," Organov told us. "This could have important implications for models of the internal structure of these planets, (their) heat budget, and chemistry."

The findings could lead to some interesting results here on Earth. That's because even though the research showed what happens to these compounds at very high pressure, we can create at least some of those pressures using current equipment, which could allow us to make them commercially on our very own planet.

"One result with a potential industrial application is that carbonic acid becomes stable at ... one gigapascal," explains Organov. "Such pressures are easily achievable on an industrial scale, which means that the previously elusive carbonic acid can be produced on the large scale. (Once) its properties are explored in sufficient detail, applications will surely follow."

Source: MIPT