X-Ray diffraction, differential scanning calorimetry, dielectric measurements and Raman studies in [C₆H₅NH₃]₃Cl SbCl₅⋅H₂O

Abstract

The tris (phenylammonium) chloride pentachloroantimonate (III) monohydrate exhibits one phase transition at (T = 217 ± 2 K): Phase (I) – 217 K → Phase (II). This transition has been characterized by differential scanning calorimetry, dielectric measurements and Raman scattering on polycrystalline samples of [C₆H₅NH₃]₃Cl SbCl₅⋅H₂O. The room-temperature phase is triclinic with the following unit cell dimensions: a = 9.4283(3), b = 11.4482(3), c = 13.1748(3) Å, α = 113.493(2), β = 90.381(2), γ = 97.331(1)°. Phase I is ordered and exhibits triclinic symmetry. Hydrogen bonding, the nature and the degree of structure disorder and the mechanisms of the phase transition are discussed. The ammonium ions show orientation disorder at the high temperature.

Keywords:

• X-ray diffraction
• DSC
• Dielectrics
• Raman spectroscopy
• Dynamic orientational disorder