Pressure dependence of melting temperature and shear modulus of hcp-iron

ABSTRACT

The pressure effects on melting temperature and shear modulus of hcp-iron have been studied based on the semi-empirical approach in the Debye model. The recent well-established pressure-dependent Grüneisen parameter has been applied to derive the analytical expressions of the Debye frequency, the Debye temperature, melting temperature and shear modulus which are of importance to geophysical implications. Numerical calculations have been performed for hcp-iron as functions of pressure up to the pressure of Earth's inner core. Our calculations are compared with those of previous experimental and theoretical data showing the good and reasonable agreements. The present results contribute to the database of high pressure melting, especially Earth's inner core boundary temperature, and could also be used to verify as well as analyze the future high pressure diamond-anvil cell experiments.

KEYWORDS:

• Melting curve
• shear modulus
• high pressure
• Debye model
• Lindemann criterion

Acknowledgements

The authors gratefully acknowledge Prof. Vu Van Hung and Prof. Nguyen Van Hung for useful comments.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Ho Khac Hieu http://orcid.org/0000-0002-0635-2889

Additional information

Funding

This research was funded by the Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number [103.01-2014.12].