The structure of liquid chlorine

Abstract

We report neutron diffraction measurements of liquid chlorine at 200 K and 290 K and orthobaric densities. The scattering functions, S(K), and the radial distribution functions, g(r), are discussed by comparison with those of other homonuclear diatomic liquids like N₂, O₂, Br₂ and I₂. Strong orientational correlations, found in both thermodynamic states, are suggested to be related mainly to the quadrupolar interaction. The shapes of the g(r) functions and the number of first neighbours strongly indicate that, at short distance in the liquid, we have correlations among first neighbouring molecules very similar to that we find in solid chlorine. Some implications for the σ value used in the 2LJC intermolecular potential are discussed, and consequences are also indicated for the MD experiments already done to simulate the liquid halogens.