Proton dynamics and phase transitions in doped ice lattices

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Apart from hexagonal ice, so abundant on earth, 15 further crystalline polymorphs of ice are known and several more are predicted. Ice XIII, ice XIV, and ice XV were produced only in the last seven years by doping previously known ice phases. It is well established that defects such as HCl and KOH can accelerate the proton dynamics on ice lattices by orders of magnitude thereby, e.g., facilitating otherwise kinetically inhibited phase transitions. The impact of doping on the motional processes within various ice phases is, however, far from being understood and is to be studied by combining dielectric spectroscopy with magnetic resonance techniques and accompanying computer simulations. For cubic ice, clathrat-like ice lattices, as well as for metastable high-pressure ice phases that can be stabilized at ambient pressure below temperatures of about 150 K, it is the goal of this project to unravel the dynamics of ice-specific point defects, to understand the transformation kinetics of various phases also within large electrical fields, and to clarify the microscopic nature of the motional mechanisms accompanying the phase transitions of ice.