Computationally Guided Discovery of the Sulfide LiAlS in the Li-Al-S Phase Field: Structure and Lithium Conductivity.

With the goal of finding new lithium solid electrolytes by a combined computational-experimental method, the exploration of the Li-Al-O-S phase field resulted in the discovery of a new sulfide LiAlS. The structure of the new phase was determined through an approach combining synchrotron X-ray and neutron diffraction with Li and Al magic-angle spinning nuclear magnetic resonance spectroscopy and revealed to be a highly ordered cationic polyhedral network within a sulfide anion -type sublattice. The originality of the structure relies on the presence of AlS repeating dimer units consisting of two edge-shared Al tetrahedra.