Ice XI is the proton-ordered form of Ice Ih and was identified in 1972 by Shuji Kawada (Ref. 1). In principle ice XI forms when ice Ih is colled to below 72K.
- Shuji Kawada "Dielectric Dispersion and Phase Transition of KOH Doped Ice", Journal of the Physical Society of Japan 32 pp. 1442-1442 (1972)
- Carlos Vega, Carl McBride, Eduardo Sanz and Jose L. F. Abascal "Radial distribution functions and densities for the SPC/E, TIP4P and TIP5P models for liquid water and ices Ih, Ic, II, III, IV, V, VI, VII, VIII, IX, XI and XII", Physical Chemistry Chemical Physics 7 pp. 1450 - 1456 (2005)