What relativistic theory can teach us about the origin of biological homochirality

The origin of biological homochirality remains one of the most enduring open questions in science. The Sasselov group recently proposed a hypothesis based on the enantioselective crystallization of RNA precursors on magnetite surfaces, achieving chiral resolution in laboratory experiments. While these results provide compelling evidence, the underlying mechanism remains unknown. Sasselov suggested that the process is driven by chiral-induced spin selectivity (CISS), which refers to the ability of chiral molecules to spin-polarize transmitted electrons according to the molecular handedness. CISS requires three elements: molecular chirality, electron spin, and an interaction mechanism linking the two. An immediate candidate for mediating such interaction is spin-orbit coupling (SOC), a relativistic effect in which the electron spin interacts with the magnetic induction generated by its motion relative to the nuclei. However, state-of-the-art quantum chemistry methods fail to capture the interplay between molecular chirality and spin, and preliminary simulations based on electron dynamics in a static nuclear frame have been unsuccessful. This reflects both the limitations of current SOC treatments and the neglect of electron–nuclear angular momentum transfer in the Born–Oppenheimer approximation. To overcome these shortcomings, this project will combine relativistic electronic structure theory with non-adiabatic molecular dynamics. Specifically, we will develop GPU-accelerated relativistic electronic structure methods that are efficient enough for use in non-adiabatic simulations yet sufficiently accurate to capture CISS. These tools will be integrated with first-principles non-adiabatic dynamics codes to simulate the enantioselective crystallization, as proposed by the Sasselov group.