The π‐hole tetrel bond between X2TO and CO2: Substituent effects and its potential adsorptivity for CO2

Abstract

AbstractQuantum chemical calculations are applied to study the complexes between X2TO (X = H, F, Cl, Br, CH3; T = C, Si, Ge, Sn) and CO2. The carbon atom of CO2 as a Lewis acid participates in the C···O carbon bond, whereas its oxygen atom as a base engages in the O···T tetrel bond with X2TO. Most of complexes are stabilized by a combination of both C···O and O···T interactions. The interaction energy increases in the T = C < Ge < Sn < Si sequence for most complexes. Both the electron‐withdrawing halogen group and the electron‐donating methyl group increase the interaction energy, up to 51 kJ/mol in F2SiO···CO2. One F2SiO molecule can bind with different numbers of CO2 molecules (1–4); as the number of CO2 molecules increases, the average interaction energy for each CO2 decreases and each CO2 molecule can contribute with at least 27 kJ/mol. Therefore, silicon‐containing molecules are good absorbents for CO2.