Erratum: A solid–solid phase transition in carbon dioxide at high pressures and intermediate temperatures

Water-carbon dioxide mixtures at high temperatures and pressures as studied by infrared and Raman spectroscopies

The state of aggregation of water dissolved in supercritical carbon dioxide has been investigated under isobaric heating (T=40-340°C, P=250 bar) using infrared absorption and Raman scattering spectroscopies. Quantitative analysis of experimental spectra has shown that below 100°C, water exists only in its monomeric form (solitary water surrounded by CO2 molecules) whereas H-bonded species, name...

New phase diagram of oxygen at high pressures and temperatures.

In situ high P-T Raman measurements and optical observations of solid and fluid oxygen up to 1250 K between 8 and 25 GPa reveal the existence of a new molecular phase eta and strikingly unusual behavior of the melting curve. Three triple points were also identified in the P-T domain of the new phase. The data give a direct measure of the melting curve that greatly extends previous optical inves...

Fluids at high pressures and temperatures

With high pressures, supercritical fluids can be studied over a very wide range of density. Fluids with strongly interacting polar molecules for example water are of particular interest. Results for several thermophysical properties are discussed. Density, dielectric constant and self—ionization of water have been determined or predicted to 1000 °C. Beyond 20 GPa very hot water appears to becom...

Electrical conductivity of wadsleyite at high temperatures and high pressures

New phases of N2O4 at high pressures and high temperatures

High P–T studies of molecular N2O4 using Raman, synchrotron infrared, and X-ray diffraction measurements reveal several new phenomena. Significant changes in the vibrational spectra indicate a phase transition at about 12 GPa. The X-ray diffraction measurements show that the material remains cubic through the transition. We ascribe the transition to a change in the molecular geometry of N2O4 wi...