The crystal structures and phase behaviour of cyclohexene oxide

The phase II crystal structure of perdeuterated cyclohexene oxide has been solved from neutron powder diffraction data at 5 K utilising a simulated annealing method. The structure is triclinic, space group P 1 ¯ , with a unit cell volume of 268 Å3. The refined molecular conformation is shown to be in close agreement with recent ab initio calculations. The p–T phase diagram determined using DTA and details of the phase I structure are also reported.