Computational insights into CO2 binding reactions by intramolecular geminal group-IV+/phosphorus- and zirconium+/group-15-based frustrated Lewis pairs

Abstract

In order to reduce global warming, there is growing interest in the design of frustrated Lewis pair (FLP) molecules for CO₂ capture. This research aims to investigate the influence of group IV (M) or group 15 (G15) elements on the reactivity of intramolecular geminal M⁺/G15-based frustrated Lewis pair (FLP) molecules in CO₂ capture. Theoretical findings suggest that M⁺/P-FLP, Zr⁺/P-FLP, Zr⁺/As-FLP, and Zr⁺/Sb-FLP can readily undergo CO₂ capture reactions without difficulty. Furthermore, Zr⁺/As-FLP and Zr⁺/Sb-FLP are predicted to undergo reversible CO₂ binding reactions. Interestingly, our theoretical results suggest that the M-P bond length in isolated M⁺/P-FLP can serve as a criterion for assessing the free activation and free reaction energy of CO₂ binding. To investigate the physical factors governing the reactivity trends for the capture of CO₂ reactions by intramolecular geminal M⁺/G15-FLP, we employed frontier molecular orbital theory, energy decomposition analysis in conjunction with natural orbitals and chemical valence, and the activation strain model. Our theoretical information can assist experimental chemists in applying key factors in the design and synthesis of novel intramolecular geminal M⁺/G15-FLP molecules.