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High-pressure molecular phases of solid carbon dioxide

S. A. Bonev·F. Gygi·T. Ogitsu·G. Galli
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Abstract

We present a theoretical study of solid carbon dioxide up to 50GPa and 1500K using first-principles calculations. In this pressure-temperature range, interpretations of recent experiments have suggested the existence of CO2 phases which are intermediate between molecular and covalent-bonded solids. We reexamine the concept of intermediate phases in the CO2 phase diagram and propose instead molecular structures, which provide an excellent agreement with measurements.

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S. A. Bonev, F. Gygi, T. Ogitsu, G. Galli. 2003-05-16. High-pressure molecular phases of solid carbon dioxide. https://doi.org/10.1103/physrevlett.91.065501

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