In situ observations of a high-pressure phase of H2O ice

I.-M. Chou; J.G. Blank; A.F. Goncharov; Ho-kwang Mao; R.J. Hemley

doi:10.1126/science.281.5378.809

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In situ observations of a high-pressure phase of H2O ice

I.-M. Chou·J.G. Blank·A.F. Goncharov·Ho-kwang Mao·R.J. Hemley

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Abstract

A previously unknown solid phase of H2O has been identified by its peculiar growth patterns, distinct pressure-temperature melting relations, and vibrational Raman spectra. Morphologies of ice crystals and their pressure-temperature melting relations were directly observed in a hydrothermal diamond-anvil cell for H2O bulk densities between 1203 and 1257 kilograms per cubic meter at temperatures between -10??and 50??C. Under these conditions, four different ice forms were observed to melt: two stable phases, ice V and ice VI, and two metastable phases, ice IV and the new ice phase. The Raman spectra and crystal morphology are consistent with a disordered anisotropic structure with some similarities to ice VI.

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I.-M. Chou, J.G. Blank, A.F. Goncharov, Ho-kwang Mao, R.J. Hemley. 1998. In situ observations of a high-pressure phase of H2O ice. https://doi.org/10.1126/science.281.5378.809

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