The plastic state of C2Cl6

A model structure of the plastic phase of C2Cl6 generated by a Monte Carlo method is compared with single crystal neutron data. The model simulates the bcc-structure by an (8 + 1) molecular cluster with a gaussian a priori molecular centre of mass distribution and hard core Cl-Cl interaction. The effective closest Cl-Cl approach is about 10 per cent smaller than the van der Waals radius observed in the low temperature normal crystalline phase of C2Cl6. The effect of the hard core interaction on the distribution of the molecular axes, the density of Cl, and the centre of mass distribution is clearly demonstrated.