TY - JOUR
T1 - Pressure dependence of hydrogen bonding in a novel H2O-H2 clathrate
AU - Vos, Willem L.
AU - Finger, Larry W.
AU - Hemley, Russell J.
AU - Mao, Ho Kwang
PY - 1996/8/2
Y1 - 1996/8/2
N2 - We have carried out Raman spectroscopy and X-ray diffraction to 60 GPa of the 1: 1 H2O: H2 clathrate hydrate, which has water molecules in an arrangement similar to pure ices Ic and VII. The pressure dependence of both the vO-H frequency and the intermolecular distance dO-H...O is significantly larger than in pure ice: unexpectedly, both dependencies can be mapped onto those of pure ice by doubling the pressure. Nevertheless, the correlation between vO-H and dO-H...O is the same as in pure ice, making the clathrate a model system for ice at pressures reduced by a factor 2. Thus, the transition to a phase with symmetric hydrogen bonds probably occurs in the range 30-40 GPa, which is significantly lower than that for H2O.
AB - We have carried out Raman spectroscopy and X-ray diffraction to 60 GPa of the 1: 1 H2O: H2 clathrate hydrate, which has water molecules in an arrangement similar to pure ices Ic and VII. The pressure dependence of both the vO-H frequency and the intermolecular distance dO-H...O is significantly larger than in pure ice: unexpectedly, both dependencies can be mapped onto those of pure ice by doubling the pressure. Nevertheless, the correlation between vO-H and dO-H...O is the same as in pure ice, making the clathrate a model system for ice at pressures reduced by a factor 2. Thus, the transition to a phase with symmetric hydrogen bonds probably occurs in the range 30-40 GPa, which is significantly lower than that for H2O.
UR - http://www.scopus.com/inward/record.url?scp=0030564692&partnerID=8YFLogxK
U2 - 10.1016/0009-2614(96)00583-0
DO - 10.1016/0009-2614(96)00583-0
M3 - Article
AN - SCOPUS:0030564692
SN - 0009-2614
VL - 257
SP - 524
EP - 530
JO - Chemical physics letters
JF - Chemical physics letters
IS - 5-6
ER -