Abstract

We present a comprehensive computational study of the crystalline phases of water ice employing force field and dispersion corrected density functional theory calculations. We construct ice structures on the basis of more than five million tetrahedral networks listed in the Treacy, Deem, and IZA databases and employ the “Sketchmap” dimensionality reduction algorithm of Ceriotti et al. [1] to examine the thus explored configuration space. Assuming no prior knowledge of the known stable phases of water ice, we classify the structures and recover all but two of ices I to XVII and ices i, 0 and the quartz phase of ice. More importantly, we identify them as the most stable representatives of their respective clusters of alike structures. We further identify nine new dynamically stable structures with competitive enthalpies including anharmonic quantum nuclear motion compared to the known phases of ice, two of which match the s-III clathrate hydrate of Huang et al. [2] and the recently identified ice XVII of del Rosso et al., [3] respectively. Finally, on this basis we further propose candidates for ices XVIII through XXIII .

[1] M. Ceriotti et al., PNAS 108 13023-13028, 2011

[2] Y. Huang et al., Science Advances 2 e1501010, 2016

[3] L. del Rosso et al., Nature Communications 7 13394, 2016