Ultra stable superatomic structure of doubly magic Ga and GaLi electrolyte.

We report the extreme thermal stability of the superatomic electronic structure for 13-atom gallium clusters and the GaLi electrolyte. Using previously-validated first-principles simulations, [K. G. Steenbergen and N. Gaston, Phys. Rev. B: Condens. Matter Mater. Phys., 2013, 88, 161402-161405] we show that the superatomic shell progression of doubly-magic Ga remains stable up to 1000 K, making this cluster an ideal candidate for high-temperature applications requiring an exceptionally stable electronic structure. Using the neutral and cationic clusters for comparison, we quantify the extent to which cluster stability (geometric and electronic) is modified through addition or subtraction of a single electron. Finally, combining 13-atom gallium with lithium, we illustrate that superatomic closed-shell GaLi exhibits the same exceptionally high thermal stability as naked Ga. For technological use as a superatomic electrolyte, we demonstrate that GaLi has a low affinity to water as well as a low Li binding energy.