Figure 6. Effective elastic constant of thin-film Li_xMoS₂ with different degrees of lithiation.

(square) decreases from 147 GPa (x=0) to 121 GPa (x=1). (diamond) increases from 22 GPa (x=0) to 32 GPa (x=0.34) and then decreases to 18 GPa (x=1). As comparison, the C₃₃ of bulk Li_xMoS₂ samples (circle) are also plotted. C₃₃ gradually changes from 52 GPa (x=0) to 58 GPa (x=0.86) with a transition point at x≈0.34. The error bars are calculated by taking into account the experimental errors and the systematic errors that propagate from uncertainties in the Al film thickness, Li_xMoS₂ film density and the input elastic constants.