Electrified Gold/Ice interface*

Hexagonal ice (ice Ih), also known as ordinary ice, displays a variety of fascinating properties that are significant for the existence of life and the control of Earth's climate. Ice XI is the proton ordered phase of hexagonal ice Ih and it is often referred to as ferroelectric ice. Experimentally, it is difficult to observe the phase transition from ice Ih to ice XI, and  the presence of ionic impurities seems to be a prerequisite to catalyze the order-disorder phase transition. However, the presence of a surface can enhance the symmetry breaking and promote the growth of proton ordered ice layers (ice iX layers) without the need for doping. In this work we analyze the structure and electronic properties of ice Ih and XI at the interface of a gold (Au) electrode, as a function of an external bias potential applied to the electrodes. This is accomplished using a combination of Density Functional Theory (DFT) and non-equilibrium Green's functions methods (NEGF).