Figure16

Figure 16. (A) Parallel MSRDs, (B) perpendicular MSRDs and (C) anisotropy of the relative thermal vibrations for the Sc-F and Sc-Sc atomic pairs determined by EXAFS in ScF$$ _{3} $$. The lines are the corresponding best-fit Einstein models. (D) Schematic representation of the thermal ellipsoids of the relative Sc-F and Sc-Sc vibrations reconstructed from EXAFS results. These results agree with a "guitar-string" effect as the local mechanism responsible for the NTE in ScF$$ _{3} $$. Figure taken from Ref.^[65]. © ACS Publishing. Reproduced with permission. All rights reserved.