Abstract
A multiscale modelling approach has been employed to investigate the benchmark molecule in "post-combustion carbon dioxide capture" (PCC), 2-aminoethanol (MEA), with the hope to increase the insight in the conformer stability, interconnectivity and corresponding reactivity. All calculations has been carried out within a Python-ecosystem, utilising the quantum chemistry software "Python Simulations of Chemistry Framework" (PySCF) for "Density Functional Theory" (DFT) calculations using the "Unrestricted Kohn-Sham" approach. 25 conformers of MEA has been identified at COSMO/B3LYP/aug-cc-pVDZ level of theory, with five conformers exhibiting intramolecular hydrogen bonding (HB), resulting in increased stability. However, two conformers that has not been determined in resent work, could not be fully ascertained. Transition state searches has been performed for 23 conformers, revealing interconversion barrier ranging from 0.66 to 5.15 kcal mol-1. Notably, interconversions between states exhibiting HB, were found to have the lowest barrier, while interconversion of the most stable state, were found to exhibit the highest barrier of 5.15 and 4.77 kcal mol-1. Rate constants have been calculated using transition state theory (TST), and the result yielded rate constants ranging from 4.69 ·10^8 to 9.46 ·10^14 s-1. These has further been used in kinetic Monte Carlo (kMC) simulations, indicating that the states with HB were most populated. However, not all state were possible to consider, so the results from the simulations does not reflect the entire conformational diversity to its full extent. Lastly, three conformers has been examined at COSMO/B3LYP/cc-pVDZ level of theory, to determine whether the reacting conformer affects the kinetics of the reaction. While the results could point in a direction towards this, computational issues prevent conclusive findings, and further exploration is required to fully understand the impact of conformers on reaction kinetics.