A perdeuterated cryoprotectant for neutron studies and a demonstration of its use for neutron powder diffraction on L-(-)-ephedrine hemihydrate

The use of perdeuteropolyethylpropylene (d-PEP) as a cryoprotectant for neu tron studies of molecular organic solids is demonstrated by the solution of the structure of L-(-)-ephedrine hemihydrate from neutron powder diffracti on data on a sample containing 20 wt% d-PEP. It is demonstrated that no con tribution from d-PEP to the scattering is observed. Neutron diffraction stu dies of solvent-containing molecular crystals that require a perdeuterated cryoprotectant oil are thus possible.