Electronic and structural transition in $L{a}_{0.2}S{r}_{0.8}Mn{O}_3$

We investigate the interplay of the electronic and structural transition in La${}_{0.2}$Sr${}_{0.8}$MnO${}_3$. The transport and specific heat measurements exhibit unusual evolutions and signature of a first order phase transition around 265 K. Mn K-edge extended $x$-ray absorption fine structure results reveal distortion in the MnO${}_6$ octahedra even in the cubic phase and a remarkable evolution of the distortion across the phase transition. These results manifest the importance of fluctuations in Mn 3$d$ orbital occupancy and disorder in their electronic properties, which may help in understanding the orbital and spin ordering proposed in these systems.