Hybridization and covalency in the Group 2 and Group 12 metal cation/rare gas complexes

Tuttle, William; Harris, Joe; Zheng, Yu; Breckenridge, William; Wright, Timothy

Abstract

We provide a consistent set of interaction energy curves for the Group 2 (IIA) and Group 12 (IIB) metal cation/rare gas complexes, M+-RG, where M+= Be+–Ra+ and Zn+–Hg+; and RG = He–Rn. We report spectroscopic constants derived from these, compare them with available data, and discuss trends in the values. We gain insight into the interactions that occur using a range of approaches: reduced potential energy curves; charge and population analyses; molecular orbital diagrams and contour plots; and Birge-Sponer plots. Although sp hybridization occurs in the Be+-RG, Mg+-Rg and Group 12 M+-RG complexes, this appears to be minimal and covalency is the main aspect of the interaction. However, major sd hybridization occurs in the heavier Group 2 M+-RG systems, which increases their interaction energies but there is minimal covalency. Examination of Birge-Sponer plots reveals significant curvature in many cases, which we ascribe to the changing amounts of hybridization or covalency as a function of internuclear separation. This suggests why the use of a simple electrostatics-based model potential to describe the interactions is inadequate.

Citation

Tuttle, W., Harris, J., Zheng, Y., Breckenridge, W., & Wright, T. (2018). Hybridization and covalency in the Group 2 and Group 12 metal cation/rare gas complexes. Journal of Physical Chemistry A, doi:10.1021/acs.jpca.8b07139. ISSN 1089-5639

• Journal Article Type: Article
• Acceptance Date: Aug 31, 2018
• Online Publication Date: Aug 31, 2018
• Publication Date: Aug 31, 2018
• Deposit Date: Sep 3, 2018
• Publicly Available Date: Sep 1, 2019
• Print ISSN: 1089-5639
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1021/acs.jpca.8b07139
• Publisher URL: https://pubs.acs.org/doi/10.1021/acs.jpca.8b07139