Lithium insertion mechanism in SnS2

We study lithium insertion in SnS2 by means of Sn-119 Mossbauer spectroscop y, x-ray absorption spectroscopy at Sn L-I,L-III, and S K edges, and theore tical electronic structures (calculated in the density-functional theory fr amework). An insertion mechanism is derived according to the Li amount. It shows the influence of the SnS2-layered structure on the Sn reduction, part icularly the possibility of an intermediate oxidation state between Sn-IV a nd Sn-II, which is not observed during Li insertion in three-dimensional su lfides.