Physicists from the University of Illinois in Urbana have discovered a new structure of hydrogen that was previously unknown in both theoretical models and experiments. Using a combination of quantum simulation and artificial intelligence (AI), the researchers found the new structure through the Quantum Monte Carlo simulation method. This self-learning algorithm can calculate the position of significantly more atoms than other methods, resulting in more precise structure determinations. According to the results of the AI, a crystal is formed at extremely high pressures of several hundred gigapascals and temperatures above 900 Kelvin, whose hydrogen molecules are no longer almost spherical but are distorted into an egg shape. However, the existence of this structure has not yet been experimentally proven.
Despite this, the physicists are confident that the phase actually exists because the AI correctly calculated the behavior of other hydrogen structures that have already been experimentally proven at high pressures. To verify the existence of the structure, the authors plan to conduct experiments with hydrogen at high temperatures and pressures soon. However, experiments at such pressures and temperatures are very complex, and the structure is also problematic for simulations because it is not as symmetrical as other high-pressure structures of hydrogen. The crucial zero-point energy for structure simulations can therefore only be difficult to calculate.
This discovery is significant because it could lead to a better understanding of the behavior of hydrogen under extreme conditions, which could have implications for fields such as materials science and energy production. The combination of quantum simulation and AI could also be used to discover other new structures and materials that were previously unknown.
