Structure of Intermediate-range Ordering in Sodium Carboxylate Melts

Abstract

The structure of intermediate-range ordering (IRO) in sodium acetate (CH₃COONa) and sodium propionate (C₂H₅COONa) melts was investigated by X-ray diffraction (XRD) measurements. A peak of IRO was observed at 0.59 Å⁻¹ and 0.49 Å⁻¹ of Q, (d = 10.7 Å and 12.8 Å) for anhydrous sodium acetate and sodium propionate melt, respectively. The hexahydrate melts also showed a peak at the same position. The XRD measurements were also performed for mixed melts of anhydrous sodium propionate and sodium acetate in order to investigate the composition dependence of the IRO structure, from which the structure and stability of the IRO was discussed.