First-Principles Calculation of the Structure of Mercury

Michael J. Mehl

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arXiv · mtrl-th/9512003

First-Principles Calculation of the Structure of Mercury

Michael J. Mehl

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Abstract

Mercury has perhaps the strangest behavior of any of the metals. Although the other metals in column IIB have an $hcp$ ground state, mercury's ground state is the body centered tetragonal $β$Hg phase. The most common phase of mercury is the rhombohedral $α$Hg phase, which is stable from 79K to the melting point and meta-stable below 79K. Another rhombohedral phase, $γ$Hg, is believed to exist at low temperatures. First-principles calculations are used to study the energetics of the various phases of mercury. Even when partial spin-orbit effects are included, the calculations indicate that the hexagonal close packed structure is the ground state. It is suggested that a better treatment of the spin-orbit interaction might alter this result.

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Michael J. Mehl. 1995-12-19. First-Principles Calculation of the Structure of Mercury. https://arxiv.org/abs/mtrl-th/9512003

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