Investigating Far-from-equilibrium Abiotic Precipitation

Abiotic precipitation typically conforms to the formation of geometric shapes. This is seen in the many small crystals from the fast nucleation in supersaturated solutions to the large faceted structures from the slower growth in more dilute environments. Across these nano to meter length scales, the morphological traits of flat faces and sharp edges persists from the self-assembly of either atoms or of larger nanoparticles and has guided the prevailing view of precipitation in the absence of life. The near equilibrium conditions for these crystallizing systems are in stark contrast to the products forming in complex physicochemical conditions within far-from-equilibrium settings. Under such environments, surprising structures and patterns emerge. These can be achieved experimentally as in the long-standing laboratory experiment producing hollow chemical gardens, the spatial organization of Liesegang rings, and, more recently, the biomimetic precipitation of biomorphs. Understanding the physics and chemistry governing these examples will pave the way for discovering potential new systems able to achieve similar results and inform the analysis of naturally occurring examples on Earth and other planetary bodies.