Stable Tetra‐ and Penta‐Anions in the Gas Phase

Abstract

The quest for stable gas‐phase anions in highly negative charge states has been a great challenge. While multiply charged anions are stabilized in solids and liquids by compensating cations and solvation cells, respectively, stable anions containing less than a hundred atoms in the gas phase and capable of carrying charge beyond −3 is unknown. Here, we report the discovery of thermodynamically stable tetra‐ and penta‐anions, containing less than 50 and 80 atoms, respectively, in the gas phase. A universal model is developed that explains their stability in terms of the synergy between closed shell, high electron affinity, and size and predicts new highly‐charged anions by using the known charged clusters as building blocks. Synthesis of these species can open a new chapter in materials chemistry.

ThH5: An Actinide‐Containing Superhalogen Molecule

“…Superhalogens are of the form, MX k+1 , where the ligand, X, is a halogen atom and k is the nominal valence of the central electropositive metal M [2] . Jena later extended the definition of superhalogens, showing that they can exist without halogen atoms [3–5] . Thus, some hydrides, e. g., AlH 4 , came to be classified as superhalogens, since as such, they readily formed their anionic counterparts, i. e., AlH 4 − [6] .…”

Ligand stabilization of manganocene dianions – in defiance of the 18-electron rule

“…This study demonstrates the power of the ligands in determining the stability of a complex and the role they play in the rational design of multiply charged species. 40,41 Conflicts of interest…”

Realization of the Zn3+ oxidation state

“…Thanks to the recent progress in the study of multiply-charged clusters [15][16][17][18], it is now possible to choose a single cluster which is highly stable as a trianion in the gas phase, to interact with Zn. This will avoid the challenges of using three moieties to react with Zn, as depicted above.…”

“…Indeed, with the calculated third electron affinity of 2.65 eV, BeB 11 (CN) 12 3-is one of the most stable trianions thus far. In a subsequent paper [18], two of the current authors formulated a general scheme for designing ultrastable clusters in highly charged states by modular assembling of selective stable anions carrying lesser charges. For instance, a trianion can be built by putting together a stable monoanion and a stable dianion.…”

“…These clusters can be viewed as super-pnictogens mimicking the chemistry of Group 15 elements. It is found that such clusters, capable of holding multiple additional electrons while maintaining great stability, can be designed by assembling selected cluster modules[18,23]. It has been shown recently that selected super-/pseudo-halogens with large electron affinities and linear configurations can produce highly charged clusters up to "-4" states[24].…”