Global Minimum Search and Bonding Analysis of Tl2 Hx and Tl3 Hy (x=0-6; y=0-5) Series

A remarkable distinction between boron and carbon hydrides lies in their extremely different bonding patterns and chemical reactivity, resulting in diverse areas of application. Particularly, carbon, characterized by classical two-center - two-electron bonds, gives rise to organic chemistry. In contrast, boron forms numerous exotic and non-intuitive compounds collectively called non-classical structures. It is reasonable to anticipate that other elements of Group 13 exhibit their own unusual bonding patterns; however, our knowledge of the hydride chemistry for other elements in Group 13 is much more limited, especially for the heaviest stable element, thallium. In this work, we performed a conformational analysis of Tl2 Hx and Tl3 Hy (x=0-6, y=0-5) series via Coalescence Kick global minimum search algorithm, DFT, and ab initio quantum chemistry methods; we investigated the bonding pattern using the AdNDP algorithm, thermodynamic stability, and stability toward electron detachment. All found global minimum structures are classified as non-classical structures featuring at least one multi-center bond.

Bismuth Infrared Star: Being at a Glance

Bismuth polycations have garnered significant attention from researchers due to their extraordinary and counter-intuitive structures and stoichiometries. Despite extensive experimental and theoretical investigations, understanding of the bonding in such clusters remains insufficient. An AdNDP bonding analysis was conducted to elucidate the bonding characteristics using both homoatomic and heteroatomic bismuth clusters with various stoichiometries. Analysis of the calculated nucleus-independent chemical shift data confirmed the aromatic nature of these species. Universal bonding patterns were identified that can be applied to a range of homoatomic and heteroatomic bismuth clusters. Additionally, calculations of absorbance and fluorescence spectra were performed to gain insights into the near-infrared emission and establish a potential correlation between absorbance and the identified bonding patterns.