Smallest Endohedral Metallofullerenes [Mg@C20]n (n = 4, 2, 0, -2, and -4): Endo-Ionic Interaction in Superatoms

Jiarui Li; Rui Wang; Wanrong Huang; Yu Zhu; Boon K Teo; Zhigang Wang

doi:10.1021/acs.jpclett.3c00445

Smallest Endohedral Metallofullerenes [Mg@C₂₀]ⁿ (n = 4, 2, 0, -2, and -4): Endo-Ionic Interaction in Superatoms

J Phys Chem Lett. 2023 Mar 23;14(11):2862-2868. doi: 10.1021/acs.jpclett.3c00445. Epub 2023 Mar 15.

Authors

Jiarui Li¹, Rui Wang¹, Wanrong Huang¹, Yu Zhu¹, Boon K Teo², Zhigang Wang^{1

3

4}

Affiliations

¹ Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China.
² College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
³ International Center for Computational Method & Software, College of Physics, Jilin University, Changchun 130012, China.
⁴ Institute of Theoretical Chemistry, Jilin University, Changchun 130023, China.

PMID: 36920152
DOI: 10.1021/acs.jpclett.3c00445

Abstract

This work reports a series of endohedral metallofullerene superatoms [Mg@C₂₀]ⁿ, where n = 4, 2, 0, -2, and -4. It was found that Mg transfers virtually all of its 3s electrons to the C₂₀ shell, resulting in the ionic states of Mg²⁺@[C₂₀]^n-2. Detailed calculations revealed that the superatomic electronic configuration of these clusters is 1S²1P⁶1D¹⁰1F^4-n. The first nine superatomic molecular orbitals (SAMOs), 1S²1P⁶1D¹⁰, housed with 18 electrons, are largely based on [C₂₀]^n-2 with small contributions from magnesium, while the outmost SAMOs, 1F^4-n, with 4 - n extra electrons, reside solely on [C₂₀]^n-2. The interaction between the Mg²⁺ ion and [C₂₀]^n-2 was found to be predominately ionic in character. Furthermore, ultraviolet-visible spectra provide a theoretical basis for fingerprinting these clusters. It is hoped that this work will encourage the synthetic pursuit of these smallest superatomic systems.