Diamonds, renowned as Earth’s hardest naturally occurring substance, face a challenge from a theoretical material deemed even tougher, according to a recent computational modeling effort. Dubbed ‘super-diamonds,’ this hypothetical substance could potentially exist in extraterrestrial realms and perhaps, eventually, be synthesized on our planet.
Super-diamonds, akin to conventional diamonds, derive from carbon atoms. This specific carbon phase, consisting of eight atoms, is believed to remain stable under ambient conditions, raising the possibility of its existence within Earth-based laboratories.
Known as BC8, this particular phase is a high-pressure variant commonly observed in materials like silicon and germanium. The latest computational simulations, conducted using Frontier, the world’s fastest exascale supercomputer, indicate the plausibility of carbon adopting this structure.
Frontier’s calculations suggest that BC8 carbon boasts a compression resistance approximately 30% higher than traditional diamonds. The findings, detailing this super-hard material, were recently unveiled in The Journal of Physical Chemistry Letters.
Marius Millot, a co-author of the study and researcher at Lawrence Livermore National Laboratory (LLNL), remarked on the persistent pursuit of synthesizing this elusive carbon crystalline phase. Despite numerous attempts, including prior endeavors at the National Ignition Facility (NIF), BC8 carbon remains elusive but may find a home in carbon-rich exoplanets, as proposed by Millot.
This isn’t the first instance suggesting the existence of ultra-hard materials beyond Earth. In 2022, researchers identified evidence of lonsdaleite, a rare diamond variant, within meteorite fragments.
Advances in space-based observation, such as the Webb Space Telescope, are expanding our understanding of carbon-rich exoplanets. NASA’s future plans, including the Habitable Worlds Observatory, aim to delve further into these distant realms.
However, waiting for direct observations isn’t the sole strategy. The extreme conditions prevailing in carbon-rich exoplanets could foster the development of unique carbon structures, including super-diamonds, according to Ivan Oleynik, a physicist at the University of South Florida and senior author of the study.
While growing super-diamonds in laboratory settings remains a possibility, the journey to achieve this feat involves exploring the capabilities of LLNL’s National Ignition Facility (NIF). This endeavor, part of NIF’s Discovery Science program, holds promise for advancements in materials science, although immediate breakthroughs are not guaranteed.
