Results and findings in short
Although icosagen cations are known to interact significantly with noble gases, well-defined examples exhibiting strong binding energies indicative of covalent character, particularly for the heavier icosagens, remain scarce.
In this work, we explore the stability and bonding of a series of XeEF2+ and Xe2EF2+ (E = B–Tl) cations, focusing on global-minimum structures featuring Xe−E bonds. Ab initio calculations indicate that these species are thermodynamically viable at 298 and 398 K, with all considered dissociation pathways being endergonic. Bonding analyses reveal strong covalent Xe–icosagen interactions for B, Al, and Ga, while In and Tl form weaker bonding character that suggests more ionic interactions, as supported by the selected complementary analyses.
Fluoride ion affinities and relativistic 129Xe NMR chemical shifts further support the strong electron-withdrawing nature of the EF2+ cations. Overall, the results suggest that, beyond the previously reported XeBF2+, Xe–icosagen compounds such as XeAlF2+ and XeGaF2+ may also be experimentally accessible.
First published online: 01 Dec 2025; https://pubs.rsc.org/en/content/articlelanding/2026/cp/d5cp03397g.
Reference
Cerpa, E.; Guerrero-Cruz, J. A.; Merino, G.; Jimenez-Halla, J. O. C.; Castro, A. C.; Covalent bonding and extreme shielding in xenon–icosagen fluoride cations, Phys. Chem. Chem. Phys., 2026, 28, 271-279.
All computational data are available in the ioChem-BD repository and can be accessed via https://doi.org/10.19061/iochem-bd-6-567
Researchers and interested parties can access the dataset to facilitate further research and validation of the findings presented in this study.
Funding
- The Research Council of Norway: Hylleraas Centre (262695), FRIPRO YRT (325231).
- Computational resources from Sigma2 (nn14654k).
- Kukulcan Computing Center of Cinvestav Mérida.
- Supercomputer Centre of the University of Guanajuato.