Neutrons meet ice polymorphs

Abstract

The current epoch can be described as the ‘age of ice-rush’, as the rate of discovery of ice polymorphs, of which there are currently 20 known, has accelerated, particularly since the end of the last century. This is largely owing to advances in neutron diffraction under pressure. Neutrons can interact with light elements such as hydrogen as well as heavy elements, making neutron diffraction essential for full structural analyses of newly discovered ice polymorphs. It is especially useful for detecting crystallographic symmetry breaking due to hydrogen ordering. This review will go over the most recent technical advances in neutron-diffraction experiments and how they contribute to our understanding of ice polymorphs.