The compound Na5Li3Ti2S8 was synthesized by the reaction of Ti with a Na/Li/S

flux at 723K. Na5Li3Ti2S8 crystallizes in a new structure type with four formula

units in space group C2/c of the monoclinic system. The structure contains three

crystallographically independent Na+ cations and two crystallographically

independent Li+ cations. Na5Li3Ti2S8 possesses a channel structure which featured

two-dimensional ∞

2[LiTiS4

3-] layers built up from Li(1)S4 and TiS4 tetrahedra. The

layers, which were stacked along c, comprise eight-membered rings and sixteenmembered

rings. Na(3)+ cations were located between the eight-membered rings

and Na(1)+, Na(2)+, and Li(2)+ cations were located between the sixteen-membered

rings. These cations were each octahedrally coordinated by six S2− anions. The

ionic conductivity σT of Na5Li3Ti2S8 ranges from 8.8 x 10−6S/cm at 303K to 3.8 x

10−4S/cm at 483K. The activation energy was 0.40eV.

Synthesis, Structure, and Ionic Conductivity of Na5Li3Ti2S8. F.Q.Huang, J.Yao,

Z.Liu, J.Yang, J.A.Ibers: Journal of Solid State Chemistry, 2008, 181[4], 837-41