CO₂Aggregation on Monoethanolamine: Observations from Rotational Spectroscopy

Abstract

The initial stages of the gas-phase nucleation between CO 2 and monoethanolamine were investigated via broadband rotational spectroscopy with the aid of extensive theoretical structure sampling. Sub-nanometer-scale aggregation patterns of monoethanolamine-(CO 2 ) n , n = 1-4, were identified. An interesting competition between the monoethanolamine intramolecular hydrogen bond and the intermolecular interactions between monoethanolamine and CO 2 upon cluster growth was discovered, revealing an intriguing CO 2 binding priority to the hydroxyl group over the amine group. These findings are in sharp contrast to the general results for aqueous solutions. In the quinary complex, a cap-like CO 2 tetramer was observed cooperatively surrounding the monoethanolamine. As the cluster approaches the critical size of new particle formation, the contribution of CO 2 self-assembly to the overall stability increases.

Water Arrangements upon Interaction with a Rigid Solute: Multiconfigurational Fenchone-(H2O)4–7 Hydrates

“…11−13 The development of chirped pulse Fourier transform microwave (CP-FTMW) spectroscopy, 14 with the capacity of recording large sections of the spectrum at once, has further advanced the study of microsolvated complexes, revealing a wealth of species produced in supersonic jets. Recent reports include complexes with a large number of isomers, such as limonene-(H 2 O) 1,2 , 15,16 aggregates of various sizes between difluoromethane and water, 17 propiolactone-(H 2 O) 1−5 , 5 3-methylcatechol-(H 2 O) 1−5 , 18 22 Usually more than one isomer is observed for complexes with up to three waters. For higher-order hydrates, only one isomer was observed, except for β-propiolactone-(H 2 O) 4 , 5 for which two isomers were found.…”