Hydrogenated superalkalis and their possible applications.

Superalkali species possess lower ionization energy than alkali metals, which allow them to form a variety of unusual compounds with interesting properties. Herein, we report the structures and properties of hydrogenated superalkalis (SAHs) such as FLi2H, OLi3H, and NLi4H using ab initio MP2/6-311++G(d,p) level of theory. All SAH species are found to be thermodynamically stable, which can be considered as a salt between SA cation and H‾ anion. The gas phase basicity and nonlinear optical properties (NLO) of SAH have been explored. The larger proton affinity of NLi4H isomers 1187-1226 kJ mol(-1) and significant mean hyperpolarizability 1.5 × 10(3)-3.7 × 10(3) a.u. suggest their strong basic nature and enhanced NLO properties, respectively. We have also demonstrated some possible applications of hydrogenated superalkalis, as reducing agent as well as building block of supersalts. Graphical abstract The gas phase basicity and nonlinear optical properties of hydogenated superalkalis increase with the increase in the size of superalkalis, FLi2 < OLi3 < NLi4.