Solving a Historical Puzzle

We report x-ray absorption near edge structure (XANES) measurements of four closely related perovskite materials: SrTiO3, CaTiO3, CaZrO3, and SrZrO3. This data is used to address the conceptually important, early EXAFS experiment of Perel and Deslattes. That experiment attempted to distinguish between the then-competing short-range and long-range theories of EXAFS by cross-material comparison of the EXAFS for the metal ions in the four perovskites reported here. Their inconclusive result is surprising, given the modern understanding of EXAFS. Our new measurements show strong disagreements with the prior results at multiple edges. When analyzed in qualitative, conceptual framework of the original study, our new results are in strong agreement with the short-range order theory. This solves a historical puzzle in the early scientific development of x-ray absorption spectroscopy