The quasi-liquid film on ice evidence from, and implications for contact charging events

Evidence for the existence of a quasi-liquid film on the surface of ice provided by molecular theory and experiments on ice crystal growth is supported through the interpretation of various experiments on contact electrification using ice samples. The interpretation provides a unified explanation for contact electrification in ice and suggests that the primary influence is that of the local water vapour pressure at contact sites. Effects relating to impact speed, temperature, humidity and gross surface structure that have previously been difficult to understand or reconcile, are, then, consequences of the prevailing macroscopic and microscopic conditions of each experiment. A dependence of transferred charge upon air pressure is predicted.