An Empirical Tight-Binding Model for Titanium Phase Transformations

Abstract

For a previously published study of the titanium hcp (alpha) to omega (omega) transformation, a tight-binding model was developed for titanium that accurately reproduces the structural energies and electron eigenvalues from all-electron density-functional calculations. We use a fitting method that matches the correctly symmetrized wavefuctions of the tight-binding model to those of the density-functional calculations at high symmetry points. The structural energies, elastic constants, phonon spectra, and point-defect energies predicted by our tight-binding model agree with density-functional calculations and experiment. In addition, a modification to the functional form is implemented to overcome the "collapse problem" of tight-binding, necessary for phase transformation studies and molecular dynamics simulations. The accuracy, transferability and efficiency of the model makes it particularly well suited to understanding structural transformations in titanium.

9 pages, 8 figures, 5 tables

References in corpus (7)

• Applications of a tight-binding total energy method for transition and noble metals: Elastic Constants, Vacancies, and Surfaces of Monatomic Metals
• Impurities block the alpha to omega martensitic transformation in titanium
• A New Mechanism for the Alpha to Omega Martensitic Transformation in Pure Titanium
• Systematic pathway generation and sorting in martensitic transformations: Titanium alpha to omega
• Thermal Stabilization of the HCP Phase in Titanium
• Tight-binding study of high-pressure phase transitions in titanium: alpha to omega and beyond
• Block-Diagonalization and f-electron Effects in Tight-Binding Theory

Cited by in corpus (5)

• Classical potential describes martensitic phase transformations between the $\alpha$, $\beta$ and $\omega$ titanium phases
• Anomalous thermal expansion in $\alpha$-titanium
• Density Functional Theory investigations of titanium gamma-surfaces and stacking faults
• Machine learning interatomic potential for the low-modulus Ti-Nb-Zr alloys in the vicinity of dynamical instability
• Phase transitions in titanium with an analytic bond-order potential