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arXiv · 0801.0913

High pressure-high temperature phase diagram of ammonia

Sandra Ninet·Frédéric Datchi
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Abstract

The high pressure(P)-high temperature(T) phase diagram of solid ammonia has been investigated using diamond anvil cell and resistive heating techniques. The III-IV transition line has been determined up to 20 GPa and 500 K both on compression and decompression paths. No discontinuity is observed at the expected location for the III-IV-V triple point. The melting line has been determined by visual observations of the fluid-solid equilibrium up to 9 GPa and 900 K. The experimental data is well fitted by a Simon-Glatzel equation in the covered P-T range. These transition lines and their extrapolations are compared with reported calculations.

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Sandra Ninet, Frédéric Datchi. 2008-01-07. High pressure-high temperature phase diagram of ammonia. https://doi.org/10.1063/1.2903491

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