CO2 Activation Within a Superalkali-Doped Fullerene

Giovanni Meloni; Andrea Giustini; Heejune Park

doi:10.3389/fchem.2021.712960

CO₂ Activation Within a Superalkali-Doped Fullerene

Front Chem. 2021 Jul 14:9:712960. doi: 10.3389/fchem.2021.712960. eCollection 2021.

Authors

Giovanni Meloni^{1

2}, Andrea Giustini², Heejune Park¹

Affiliations

¹ Department of Chemistry, University of San Francisco, San Francisco, CA, United States.
² Department of Physical and Chemical Sciences, Università degli Studi de L'Aquila, L'Aquila, Italy.

Abstract

With the aim of finding a suitable synthesizable superalkali species, using the B3LYP/6-31G* density functional level of theory we provide results for the interaction between the buckminsterfullerene C₆₀ and the superalkali Li₃F₂. We show that this endofullerene is stable and provides a closed environment in which the superalkali can exist and interact with CO₂. It is worthwhile to mention that the optimized Li₃F₂ structure inside C₆₀ is not the most stable C_2v isomer found for the "free" superalkali but the D_3h geometry. The binding energy at 0 K between C₆₀ and Li₃F₂ (D_3h) is computed to be 119 kJ mol^-1. Once CO₂ is introduced in the endofullerene, it is activated, and the $\hat{O C O}$ angle is bent to 132^°. This activation does not follow the previously studied CO₂ reduction by an electron transfer process from the superalkali, but it is rather an actual reaction where a F (from Li₃F₂) atom is bonded to the CO₂. From a thermodynamic analysis, both CO₂ and the encapsulated [Li₃F₂⋅CO₂] are destabilized in C₆₀ with solvation energies at 0 K of 147 and < -965 kJ mol^-1, respectively.

Keywords: CO2 activation; endofullerene; ionization energy; solvation energy; superalkali.