CATion · Exploring the Frontiers of p-block Cation Chemistry under Extreme Conditions

In this project, I will search for novel cations of the p-block elements and explore the structural landscape and behavior of p-block-cation-containing compounds under extreme conditions. Diamond-anvil cells (DAC) will be used to generate high pressures, and laser heating (LH) will be used to locally superheat the system to promote the chemical reactions and crystallization of novel phases. Recent advances in in situ multigrain synchrotron X-ray microdiffraction in combination with Raman mapping now allow detailed structural characterization of products formed during LH-DAC experiments.Such extreme conditions enable the formation of novel cations, as the usual rules of chemical bonding and molecular geometry change at high pressures. At the gigapascal range of interest, the PV contribution to Gibbs energy becomes comparable to covalent bond energies, allowing chemical reactions that are unfavorable at ambient pressure to occur. My research will focus on the emergence of different cationic species in distinct phases during the structural evolution of a heterogeneous system with fixed composition. The successful realization of the proposed research would enrich fundamental inorganic chemistry by novel textbook examples of p-block cations and novel oxidation states of p-block elements and provide valuable insights into the hitherto unknown high-pressure behavior of cationic species containing homonuclear bonds.