Selecting solvents for intensification of thermal dissociation of tri-n-octylamine hydrochloride by calculating infrared spectra from ab initio molecular dynamics

Nitrogen-hydrogen (N-H) stretching vibration modes serve as key probes in the identification of the binding strength between amine and hydrogen chloride. Their assignments give us a theoretical viewpoint that could help us select the most suitable solvent for the regeneration of extractant tri-n-octylamine by the thermal dissociation of tri-n-octylamine hydrochloride method. Through a combination of ab initio molecular dynamics (AIMD) and static normal mode analysis (NMA), as well as the experimental infrared spectra, we conclude that the AIMD simulations which include the explicit solvents agree with the thermal dissociation experimental results perfectly, whereas the NMA calculated with implicit solvents could not show the solvent effects on the v (N-H) correctly, although the general trend seems not bad.