Pentazole (N5H) as a possible catalyst for CO2 activation: Density functional theory (DFT) and ab initio molecular dynamics (AIMD) studies

Abstract

AbstractThe alarming increase in the atmospheric CO2 concentration is a matter of great concern today. Enormous attention has been devoted to search the novel and innovative approaches to recycle the CO2 evolved from the industries into useful chemicals. However, the thermodynamic stability of CO2 molecule imposes a great challenge in utilizing it as a raw material in chemical reactions. In the present investigation, an attempt has been made to scrutinize pentazole (N5H) as an effective catalyst for the CO2 activation. The fixation reaction of CO2 with ethylene oxide (oxirane) was chosen to be the prototypal model. Both the density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) studies explicitly suggest pentazole to be a promising catalyst for the activation of CO2 molecule. The energy required for the CO2 activation was found to be 35.6 kcal/mol. Also, the proton transfer step is found to be the key step in the reaction. Based on the prototypal reaction, the coupling reaction of CO2 with aziridine, propylene oxide and styrene oxide was also investigated.