Evidence of Long Range Ordering in Molten MgCI₂

Abstract

The low Q rise in the structure factor, S_T (Q), of molten MgCl₂ observed by Day and McGreevy for Q ≃ 0.3 Å⁻¹ has been confirmed by small angle neutron scattering using the D17 diffractometer at the Institut Laue Langevin. This feature is found to have a possible maximum value at Q ≃ 0.1 Å⁻¹ indicating long range ordering with a correlation length ≃ 60 Å. The results are found to be inconsistent with the possibility of oxygen contamination, so the ordering must be inherent to the liquid structure.

Key Words:

• Correlation length
• small angle scattering.