Molecular Insights into CO2 Clustering: Topologies and Driving Forces from Rotational Studies

The continuous rise in atmospheric CO₂ levels, primarily driven by anthropogenic emissions, poses a significant challenge due to its central role in global warming. Carbon capture strategies are pivotal for mitigating these impacts, yet their effectiveness critically hinges on a molecular-level understanding of CO₂ interactions and aggregation behaviors. This Perspective surveys recent advances in rotational spectroscopic studies of CO₂ aggregation, spanning from simple dimers and trimers to subnanometer-scale clusters formed with diverse partner molecules. These investigations uncover the intricate network of noncovalent interactions─particularly tetrel and hydrogen bonding, that governs CO₂ aggregation and solvation, especially in supercritical CO₂ environments. By bridging the gap between isolated molecular behavior and condensed-phase phenomena, this Perspective highlights the potential of rotational spectroscopy as a tool to guide the rational design of high-capacity CO₂ capture materials and optimize carbon capture and utilization processes.