Neutron diffraction studies of ices III and IX on underhyphen;pressure and recovered samples

摘要

Detailed structural studies using powder neutron diffraction have been carried out on ices III and IX on both underhyphen;pressure and recovered samples. The incomplete hydrogen ordering in recovered ice IX first observed by La Placaetal. is confirmed, and our studies suggest similar orderings for the underhyphen;pressure and recovered phases. Sample history was observed to influence the lattice constants of ice IX, an effect which could relate to hydrogen ordering. There is an indication that ice III is not fully disordered, a conclusion which would be consistent with independent thermodynamic measurements.