TY - JOUR
T1 - Modeling the atomic structure of very high-density amorphous ice
AU - Christie, J. K.
AU - Guthrie, M.
AU - Tulk, C. A.
AU - Benmore, C. J.
AU - Klug, D. D.
AU - Taraskin, S. N.
AU - Elliott, S. R.
PY - 2005
Y1 - 2005
N2 - The structure of very high-density amorphous (VHDA) ice has been modeled by positionally disordering three crystalline phases, namely ice IV, VI, and XII. These phases were chosen because only they are stable or metastable in the region of the ice phase diagram where VHDA ice is formed, and their densities are comparable to that of VHDA ice. An excellent fit to the medium range of the experimentally observed pair-correlation function g(r) of VHDA ice was obtained by introducing disorder into the positions of the H2O molecules, as well as small amounts of molecular rotational disorder, disorder in the O H bond lengths and disorder in the H O H bond angles. The low-k behavior of the experimental structure factor, S(k), is also very well reproduced by this disordered-crystal model. The fraction of each phase present in the best-fit disordered model is very close to that observed in the probable crystallization products of VHDA ice. In particular, only negligible amounts of ice IV are predicted, in accordance with the experimental observation.
AB - The structure of very high-density amorphous (VHDA) ice has been modeled by positionally disordering three crystalline phases, namely ice IV, VI, and XII. These phases were chosen because only they are stable or metastable in the region of the ice phase diagram where VHDA ice is formed, and their densities are comparable to that of VHDA ice. An excellent fit to the medium range of the experimentally observed pair-correlation function g(r) of VHDA ice was obtained by introducing disorder into the positions of the H2O molecules, as well as small amounts of molecular rotational disorder, disorder in the O H bond lengths and disorder in the H O H bond angles. The low-k behavior of the experimental structure factor, S(k), is also very well reproduced by this disordered-crystal model. The fraction of each phase present in the best-fit disordered model is very close to that observed in the probable crystallization products of VHDA ice. In particular, only negligible amounts of ice IV are predicted, in accordance with the experimental observation.
UR - http://www.scopus.com/inward/record.url?scp=33749159251&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.72.012201
DO - 10.1103/PhysRevB.72.012201
M3 - Article
AN - SCOPUS:33749159251
SN - 1098-0121
VL - 72
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 1
M1 - 012201
ER -