Modulating the\nAmine–CO<sub>2</sub> Interaction\nStrength: Toward Efficient Carbon Capture

This study contributes to a comprehensive understanding\nof the\ninteractions between CO<sub>2</sub> and amines at the molecular level\nby exploring the rotational spectra of binary complexes between CO<sub>2</sub> and eight different amines through pulsed-jet Fourier transform\nmicrowave spectroscopy and quantum chemical calculations. The findings\nreveal a consistent pattern in which CO<sub>2</sub> is bonded to the\namino group, primarily through a C···N tetrel bond,\nwhile being supported by C–H···O/C hydrogen\nbonds. Notably, the binding energies increase from primary through\ntertiary amines and with increasing chain length of the alkyl groups.\nThese groups are found to enhance the electron density at the amino\ngroup significantly, thereby facilitating the formation of stronger\nC···N tetrel bonds. The insights provided into how\nthe interaction strength is modulated by the geometries of amines\nare deemed essential for the design of more effective CO<sub>2</sub> adsorption materials, thus advancing carbon capture technologies.