Proton ordering in cubic ice and hexagonal ice; a potential new ice phase--XIc.
Ordinary water ice forms under ambient conditions and has two polytypes, hexagonal ice (Ih) and cubic ice (Ic). From a careful comparison of proton ordering arrangements in Ih and Ic using periodic density functional theory (DFT) and diffusion Monte Carlo (DMC) approaches, we find that the most stable arrangement of water molecules in cubic ice is isoenergetic with that of the proton ordered form of hexagonal ice (known as ice XI). We denote this potential new polytype of ice XI as XIc and discuss a possible route for preparing ice XIc.
Department of Chemistry, University College London, London, WC1H 0AJ, UK. zamaan.raza.09@ucl.ac.uk
Zamaan
Z
Raza
Dario
D
Alfè
Christoph G
CG
Salzmann
Jiří
J
Klimeš
Angelos
A
Michaelides
Ben
B
Slater