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Elasticity of (Mg,Fe)O Through the Spin Transition of Iron in the Lower Mantle
Changes in the electronic configuration of iron at high pressures toward a spin-paired state within host minerals ferropericlase and silicate perovskite may directly influence the seismic velocityExpand
Direct measurement of thermal conductivity in solid iron at planetary core conditions.
The conduction of heat through minerals and melts at extreme pressures and temperatures is of central importance to the evolution and dynamics of planets. In the cooling Earth's core, the thermalExpand
Hydrogen Clusters in Clathrate Hydrate
High-pressure Raman, infrared, x-ray, and neutron studies show that H2 and H2O mixtures crystallize into the sII clathrate structure with an approximate H2/H2O molar ratio of 1:2. The clathrate cagesExpand
Reduced Radiative Conductivity of Low-Spin (Mg,Fe)O in the Lower Mantle
Optical absorption spectra have been measured at pressures up to 80 gigapascals (GPa) for the lower-mantle oxide magnesiowüstite (Mg,Fe)O. Upon reaching the high-spin to low-spin transition of Fe2+Expand
Compression of Ice to 210 Gigapascals: Infrared Evidence for a Symmetric Hydrogen-Bonded Phase
Protonated and deuterated ices (H2O and D2O) compressed to a maximum pressure of 210 gigapascals at 85 to 300 kelvin exhibit a phase transition at 60 gigapascals in H2O ice (70 gigapascals in D2OExpand
Mixed molecular and atomic phase of dense hydrogen.
We used Raman and visible transmission spectroscopy to investigate dense hydrogen (deuterium) up to 315 (275) GPa at 300 K. At around 200 GPa, we observe the phase transformation, which we attributeExpand
Raman Spectroscopy of Dense H2O and the Transition to Symmetric Hydrogen Bonds
High-pressure Raman measurements of H{sub 2}O ice using synthetic diamond anvils reveal major changes associated with the transition to the nonmolecular, symmetric hydrogen-bonded state. AtExpand
Dynamic ionization of water under extreme conditions.
Raman spectroscopy in a laser heated diamond anvil cell and first principles molecular dynamics simulations have been used to study water in the temperature range 300 to 1500 K and at pressures to 56Expand
Radiative conductivity in the Earth’s lower mantle
Iron in crustal and mantle minerals adopts several possible oxidation states: this has implications for biogeochemical processes, oxygenation of the atmosphere and the oxidation state of the mantle.Expand
The pressure-temperature phase and transformation diagram for carbon; updated through 1994
Abstract In recent years, important advances in our understanding of the pressure-temperature phase and transformation diagram for carbon have occurred as a result of developments in bothExpand