Melting Temperature of Iron in the Core, Theory
An accurate knowledge of the melting properties of Fe is particularly important, as the temperature distribution in the core is relatively uncertain and a reliable estimate of the melting temperature of Fe at the pressure of the inner‐core boundary (ICB) puts a constraint on core temperatures. However, there is much controversy over its high pressure melting behavior (e.g., see Shen and Heinz, 1998). Static compression measurements of the melting temperature (Tm) with the diamond anvil cell (DAC) have been made up to ∼200 GPa, but even at lower pressures results for Tm disagree by several hundred kelvins. Shock experiments are at present the only available method to determine melting at higher pressures, but their interpretation is not simple, and there is a scatter of at least 2000 K in the reported Tm of Fe at ICB pressures.
Since both quantum mechanics and experiments suggest that Fe melts from the hexagonal close‐packed (hcp) structured phase in the pressure range immediately above...
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