First-principles calculations of phase transition, low elastic modulus, and superconductivity for zirconium

Abstract

The elasticity, dynamic properties, and superconductivity of $\alpha$, $\omega$, and $\beta$ Zr are investigated by using first-principles methods. Our calculated elastic constants, elastic moduli, and Debye temperatures of $\alpha$ and $\omega$ phases are in excellent agreement with experiments. Electron-phonon coupling constant $\lambda$ and electronic density of states at the Fermi level $N$(\emph{E}${}_{\mathrm{F}}$) are found to increase with pressure for these two hexagonal structures. For cubic $\beta$ phase, the critical pressure for mechanical stability is predicted to be 3.13 GPa and at \emph{P}=4 GPa the low elastic modulus ($E$=31.97 GPa) can be obtained. Besides, the critical pressure for dynamic stability of $\beta$ phase is achieved by phonon dispersion calculations to be $\sim$26 GPa. Over this pressure, $\lambda$ and $N$(\emph{E}${}_{\mathrm{F}}$) of $\beta$ phase decrease upon further compression. Our calculations show that the large value of superconducting transition temperature ${\text{T}}_{\mathrm{c}}$ at 30 GPa for $\beta$ Zr is mainly due to the TA1 soft mode. Under further compression, the soft vibrational mode will gradually fade away.

arXiv comment15 pages, 5 figures

References in corpus (2)

• Entropy driven stabilization of energetically unstable crystal structures explained from first principles theory
• Assembling the puzzle of superconducting elements: A Review

Cited by in corpus (10)

• Zirconia and hafnia polymorphs -- ground state structural properties from diffusion Monte Carlo
• First-principles calculations of phase transition, elasticity, and thermodynamic properties for TiZr alloy
• On the thermal and mechanical properties of Mg${}_{0.2}$Co${}_{0.2}$Ni${}_{0.2}$Cu${}_{0.2}$Zn${}_{0.2}$O across the high-entropy to entropy-stabilized transition
• Nonlinear elasticity of prestressed single crystals at high pressure and various elastic moduli
• Pressure-induced structural phase transitions of zirconium: An ab initio study based on statistical ensemble theory
• Benchmarking Structural Evolution Methods for Training of Machine Learned Interatomic Potentials
• ZrNb(CO) RF superconducting thin film with high critical temperature in the theoretical limit
• A survey of energies from pure metals to multi-principal element alloys
• In situ quantitative study of plastic strain-induced phase transformations under high pressure: Example for ultra-pure Zr
• Effect of vacancies on the mechanical properties of zirconium: An ab initio investigation